Holographic Messages Can Be Sent Through Quantum Technology

Posted on August 31, 2024 by Igor Mitreski

Polarized light can erase messages encoded in quantum holograms

Hong Liang, Wai Chun Wong, Tailing Ang, Jensen Lee 2024

The quantum evanescence phenomenon makes it possible to embed secure messages in holograms and selectively erase parts of them even after they have been transmitted.

Quantum optical signals are inherently secure information carriers: any interception of the message destroys the fragile quantum states that encode it. To harness this without the use of bulky devices, Jensen Lee Researchers from the University of Exeter in the UK MetasurfaceIt is a 2D material engineered with special properties to create quantum holograms.

Holograms encode complex information that can be restored when light is shone on it. For example, when light hits a 2D holographic paper card at the right angle, a 3D image appears. To create quantum holograms, researchers encoded information in the quantum state of particles of light, or photons.

First, they used a laser to emit two photons from a special crystal that were tightly bound by quantum entanglement. The photons traveled along separate paths, with only one encountering the metasurface along the way. Thousands of tiny components on the metasurface, like nano-sized bumps, altered the photon’s quantum state in a preprogrammed way, encoding a holographic image into it.

The partner photon encountered a polarizing filter, which controlled which parts of the hologram appeared and which disappeared. The first photon’s state was a superposition of holograms, so it contained different variations of the message at the same time. Because the photons were in an entangled state, polarizing the second photon affected the image the other photon created when it hit the camera. For example, a test hologram contained the letters H, D, V, and A, but adding a filter for horizontal polarization caused the letter H to disappear from the final image.

Li says metasurfaces could be used to encode more complex information into photons, for example as part of quantum cryptography protocols. He calls the research SPIE Optics + Photonics Conference August 21st, San Diego, California.

“Everyone dreams of quantum technology going from square metres on a table to being compact enough to fit in a smartphone, and metasurfaces seem like a good way to achieve that. [about that]” Andrew Forbes A researcher at the University of Witwatersrand in South Africa, said quantum holograms like the one used in this experiment could also be used to image tiny biological structures in the rapidly expanding medical field.

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Source: www.newscientist.com

Multiple nations implement baffling export restrictions on quantum computers

Posted on July 4, 2024 by Igor Mitreski

Exports of quantum computers are restricted in many countries

Saigh Anys/Shutterstock

As a result of secret international negotiations, governments around the world have imposed identical export controls on quantum computers while refusing to disclose the scientific rationale behind the controls. Although quantum computers could theoretically threaten national security by breaking encryption technology, even the most advanced quantum computers currently publicly available are too small and error-prone to achieve this, making the bans seem pointless.

The UK: Quantum computers with more than 34 quantum bits (qubits) and error rates below a certain threshold. The intention seems to be to limit machines with certain capabilities, but the UK government has not stated this explicitly. New Scientist A Freedom of Information request seeking the basis for these figures was denied on national security grounds.

France has also imposed similar export controls. Quantum Bits The numbers and error rates are also improving, as are Spain and the Netherlands. Having the same limits across European countries might suggest EU regulation, but this is not the case. A spokesperson for the European Commission said: New Scientist EU member states are free to adopt national, rather than bloc-wide, measures when it comes to export controls. “The recent quantum computer restrictions by Spain and France are an example of such national measures,” they said. They declined to explain why the figures for the EU's various export bans are completely consistent if these decisions were taken independently.

A spokesman for the French Embassy in London said: New Scientist The limits were set at a level “likely to indicate a cyber risk,” they said. They noted that the regulations are the same in France, the UK, the Netherlands and Spain because of “multilateral negotiations that took place over several years under the Wassenaar Arrangement.”

“The limits chosen are based on scientific analysis of the performance of quantum computers,” the spokesperson said. New ScientistBut when asked for clarification about who carried out the analysis and whether its findings would be made public, a spokesman declined to comment further.

of Wassenaar Agreement The system, which is followed by 42 participating countries including EU member states, the UK, the US, Canada, Russia, Australia, New Zealand and Switzerland, controls the export of items with potential military applications, known as dual-use technologies. The export ban on quantum computers also includes similar language regarding 34 qubits..

New Scientist We wrote to dozens of Wassenaar member states asking whether there was quantum-computer-level research that posed a risk to export, whether it had been made public, and who had conducted it. Only a few countries responded.

“We closely monitor other countries as they introduce national restrictions on certain technologies,” a spokesperson for the Swiss Federal Ministry of Economic Affairs, Education and Research said, “but in specific cases it is already possible to block the export of such technologies using existing mechanisms.”

“We are closely following the Wassenaar discussions on the exact technical control parameters for quantum.” Milan Godin, Belgian Advisor to the EU Working Party on Dual-Use Goods, Belgium. China does not appear to have implemented its own export controls yet, but Godin said quantum computers are a dual-use technology. It has the potential to crack commercial or government codes, and its speed could ultimately enable militaries to plan faster and better, including for nuclear missile attacks.

A spokesperson for Germany's Federal Office for Economics and Export Control confirmed that the export restrictions on quantum computers are the result of negotiations under the Wassenaar Agreement, but Germany does not appear to have implemented any restrictions. “The negotiations are confidential and unfortunately we cannot provide any details or information about the considerations of the restrictions,” the spokesperson said.

Christopher MonroeThe co-founder of quantum computing company IonQ said industry participants have been aware of similar bans and are discussing their criteria, but he doesn't know where they come from.

“I don't know who decided the logic behind these numbers,” he says, but it may have something to do with the threshold for simulating a quantum computer with a regular computer. This gets exponentially harder as the number of qubits increases, so Monroe thinks the rationale behind the ban may be to limit quantum computers that are too advanced to simulate, even though such devices have no practical use.

“It would be a mistake to think that just because we can't simulate the behavior of a quantum computer doesn't mean it's useful, and severely restricting research into advances in this grey area would certainly stifle innovation,” he says.

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Source: www.newscientist.com

Quantum entanglement used by physicists to measure Earth’s rotation

Posted on June 14, 2024 by Igor Mitreski

Physicists at the University of Vienna have used a maximally entangled quantum state of light paths in a large interferometer to experimentally measure the speed of the Earth’s rotation.

Silvestri othersThey have demonstrated the largest and most precise quantum-optical Sagnac interferometer to date, sensitive enough to measure the Earth’s rotation rate. Image courtesy of Marco Di Vita.

For over a century, interferometers have been key instruments for experimentally testing fundamental physical questions.

They disproved the ether as a light-transmitting medium, helped establish the theory of special relativity, and made it possible to measure tiny ripples in space-time itself known as gravitational waves.

Recent technological advances allow interferometers to work with a variety of quantum systems, including electrons, neutrons, atoms, superfluids, and Bose-Einstein condensates.

“When two or more particles are entangled, only the overall state is known; the states of the individual particles remain uncertain until they are measured,” said co-first author Dr. Philip Walther and his colleagues.

“Using this allows us to get more information per measurement than we would without it.”

“But the extremely delicate nature of quantum entanglement has prevented the expected leap in sensitivity.”

For their study, the authors built a large fiber-optic Sagnac interferometer that was stable with low noise for several hours.

This allows the detection of entangled photon pairs with a sufficiently high quality to exceed the rotational precision of conventional quantum-optical Sagnac interferometers by a factor of 1000.

“In a Sagnac interferometer, two particles moving in opposite directions on a rotating closed path reach a starting point at different times,” the researchers explained.

“When you have two entangled particles, you get a spooky situation: they behave like a single particle testing both directions simultaneously, accumulating twice the time delay compared to a scenario where no entanglement exists.”

“This unique property is known as super-resolution.”

In the experiment, two entangled photons propagated through a 2 km long optical fiber wound around a giant coil, creating an interferometer with an effective area of more than 700 m2.

The biggest hurdle the team faced was isolating and extracting the Earth’s stable rotation signal.

“The crux of the problem lies in establishing a measurement reference point where light is not affected by the Earth’s rotation,” said Dr Raffaele Silvestri, lead author of the study.

“Since we can’t stop the Earth’s rotation, we devised a workaround: split the optical fiber into two equal-length coils and connect them through an optical switch.”

“By switching it on and off, we were able to effectively cancel the rotation signal, which also increased the stability of larger equipment.”

“We’re basically tricking light into thinking it’s in a non-rotating universe.”

The research team succeeded in observing the effect of the Earth’s rotation on a maximally entangled two-photon state.

This confirms the interplay between rotating reference systems and quantum entanglement, as described in Einstein’s special theory of relativity and quantum mechanics, and represents a thousand-fold improvement in precision compared to previous experiments.

“A century after the first observations of the Earth’s rotation using light, this is an important milestone in that the entanglement of individual quanta of light is finally in the same region of sensitivity,” said co-first author Dr Haokun Yu.

“We believe that our findings and methods lay the foundation for further improving the rotational sensitivity of entanglement-based sensors.”

“This could pave the way for future experiments to test the behaviour of quantum entanglement through curves in space-time,” Dr Walther said.

Team work Published in a journal Scientific advances.

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Raffaele Silvestri others2024. Experimental Observation of Earth’s Rotation through Quantum Entanglement. Science Advances 10(24); doi: 10.1126/sciadv.ado0215

Source: www.sci.news

Enhancing Quantum Communication Devices with Liquid Crystals

Posted on June 13, 2024 by Igor Mitreski

Quantum light is generated when a laser is shone on certain crystals

Jaka Waxwing

The liquid crystals found in television screens have made it easy to produce quantum light.

Light, with its quantum properties, is important for many future technologies: such entangled particles in light could help build quantum communication networks that support an unhackable internet, as well as quantum imaging techniques for biomedical applications. Matyas Humar Despite these advanced applications, the method for generating quantum light has remained largely unchanged for 60 years, says a researcher at the Jozef Stefan Institute in Slovenia. He and his colleagues have devised a way to generate quantum light using liquid crystals.

Team Members Vitaly Sultanov Researchers at the Max Planck Institute in Germany say that traditionally, researchers shine a laser on special crystals to make them emit quantum light. In this technique, the structure of the crystal determines the properties of the light it emits, which in turn determines how it can be used. The only way to change these properties is to redo the experiment with new crystals, which is costly, time-consuming and impractical.

To get around this, the researchers used liquid crystals, a material made of rod-shaped molecules that can wobble like a liquid but adopt unusual arrangements like more conventional crystals. By exposing the liquid crystal to an electric field, they can tune its structure, and thus the properties of the quanta of light it emits when illuminated with a laser.

“In this respect, liquid crystals are the perfect material,” says Sultanov.

After several experiments, his team found that liquid crystals were much easier to tune than solid liquid crystals, and nearly as efficient at producing light filled with entangled particles.

“While the generated photons could conceivably have been produced using conventional crystals, the tunability of the entanglement could not,” he said. Miles Padgett “These advances are [quantum] “Imaging, Communication, Sensing”

Maria ChekhovaResearchers, also from the Max Planck Institute, say that using liquid crystals in quantum communication devices could make it easier to send information over multiple channels at once, because the liquid crystals can be tuned to produce quantum states of light that can encode large amounts of information in many of their properties.

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Source: www.newscientist.com

Australia invests A$1 billion into PsiQuantum for quantum computing efforts

Posted on April 30, 2024 by Igor Mitreski

PsiQuantum silicon photonic chips

Psi Quantum

The Australian government has announced it will invest nearly A$1 billion in developing quantum computers, staking its claim in a race currently dominated by the United States and China.

Headquartered in the US, PsiQuantum was co-founded by a team including two Australian researchers and has received funding from both the Australian Federal and Queensland Governments of A$470 million, for a total of A$940 million ($600 million). The project will receive funding of $13 million. In return, the company will build and operate a next-generation quantum computer in Brisbane, Australia.

stephen bartlett Researchers at the University of Sydney said the announcement amounted to Australia asserting sovereign capabilities in quantum computing and building a quantum technology ecosystem.

“What I'm really excited about about this is that the size of the investment means we're serious,” Bartlett says. Big technology companies such as IBM, Google and Microsoft are investing billions of dollars in quantum computing, but Australian funding makes PsiQuantum one of the world's largest dedicated quantum computing companies.

Quantum computers offer the possibility of completing some tasks much faster than regular computers. So far, such capabilities have only been demonstrated in non-practical problems, but as research teams in the U.S., China and elsewhere race to build larger and less error-prone machines, they are becoming increasingly common. It is hoped that this will begin to prove useful.

Many teams have built quantum computers based on superconductors, but PsiQuantum's approach involves particles of light called photons, which were thought to be difficult to scale up. However, ahead of the Australian announcement, PsiQuantum Published a paper The paper details how standard semiconductor manufacturing equipment, of the type used to make regular computer chips, could be used to build the photonic chips needed for quantum machines.

Australia has exported generations of quantum researchers, including the co-founders of PsiQuantum. Jeremy O'Brien and Terry Rudolph. Mr Bartlett said government investment could allow these scientists to return to Australia and start building their careers here. “Australia is saying we have a seat at the big table when it comes to quantum computing.”

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Source: www.newscientist.com

Utilizing Quantum Forces for Automated Assembly of Small Devices

Posted on April 24, 2024 by Igor Mitreski

Triangular gold flakes can be manipulated using mysterious quantum forces

George Zograf

A tiny gold device for controlling light is built using strange quantum effects hidden in seemingly empty space.

In 1948, physicist Hendrik Casimir theorized that when objects are brought close together in space, some objects experience a very weak gravitational pull due to imperceptible flickering of quantum fields in the gaps between them. Ta. Researchers then confirmed this Casimir effect in the laboratory. Betul Kyucukoz and his colleagues at Sweden’s Chalmers University of Technology have found a way to make this useful.

They wanted to build a cavity that would trap the light using two pieces of gold placed parallel to each other, so that the light would bounce back and forth between them and would not be able to escape. First, we created the bottom edge of the cavity by transferring triangular gold flakes ranging in size from 4 to 10 microns onto a small piece of glass. The top end of the cavity also contained a triangular gold flake, but instead of holding it in place with an instrument, the researchers attached it to the glass in a salt water solution containing an additional triangular gold flake. The gold flakes were then dipped in and then allowed to develop. Instead, work naturally.

One of those forces was the electrostatic force caused by the charge associated with the dissolved salt. Another is the Casimir effect. Kyuchkoz said he observed the experiment under the microscope many times and could always see the Casimir effect in action. This causes the floating gold flakes to move towards the gold flake where one is imprinted on the glass, and then he moves over the imprinted gold flake until the triangular footprints of the two flakes match. It was rotated.

This completes the assembly of a cavity that can trap light. The researchers were able to significantly control the cavity formation process, Kyucukoz said. For example, by using different concentrations of salt, we can adjust the strength of the electrostatic force so that the distance between the flakes is different for each cavity, creating cavities with slightly different dimensions of 100-200 nanometers. It can trap colored light.

Raul Esquivel Sirbento The professor at the National Autonomous University of Mexico said the idea of self-assembly, likened to throwing a Lego set into a pot and a structure emerges without having to manually press the pieces together, is not new. But he said his team’s experiment was more detailed and controlled than previous attempts to exploit the Casimir effect for similar purposes. But the Casimir effect can be very subtle, so there may be other effects here as well that haven’t been detected yet, Esquivel Servent said.

In the future, Küçüköz and his colleagues hope to use the cavity as part of more complex experiments with light, such as placing objects inside the cavity between two gold flakes.

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Source: www.newscientist.com

Microsoft and Quantinuum’s quantum computer could be the most dependable to date

Posted on April 4, 2024 by Igor Mitreski

Quantinuum H2 chip

Quantinum

Microsoft and quantum computing company Quantinuum claim to have developed a quantum computer with unprecedented levels of reliability. The ability to correct its own errors could be a step toward more practical quantum computers in the near future.

“What we did here gave me goosebumps. We showed that error correction is reproducible, works, and is reliable.” Krista Svoir At Microsoft.

Experts have long expected the arrival of practical quantum computers that can complete calculations too complex for traditional computers. Although quantum computers have steadily grown larger and more complex, this prediction has not yet been fully realized. One big reason for this is that all modern quantum computers are subject to errors, and researchers have found that it is technically difficult to implement algorithms to detect and correct errors during calculations. That’s it.

The new experiment could be an important step toward overcoming this error problem. The researchers say that on his H2 quantum processor at Quantinuum, he ran more than 14,000 individual calculation routines without making a single error.

Errors occur even in classical computers, but error correction can be coded into programs by creating backup copies of the information being processed. This approach is not possible with quantum computing because quantum information cannot be copied. Instead, researchers distributed it across a group of connected qubits, or qubits, creating what are known as logical qubits. Microsoft and the Quantinuum team created four of these logical qubits using 30 qubits.

Svore said a process developed by Microsoft was used to generate these logical qubits, allowing them to run error-free, or fault-tolerant, experiments repeatedly. Typically, individual qubits are easily disturbed, but at the level of logical qubits, researchers were able to repeatedly detect and correct errors.

The approach was so successful, they say, that four logical qubits produced only 0.125 percent of the errors that would occur if 30 qubits were left ungrouped. This means that ungrouped qubits generate as many as 800 errors for every one error generated by a logical qubit.

“Having a logical error rate that is 800 times lower than that of physical qubits is a huge advance in the field and brings us one step closer to fault-tolerant quantum computing,” he said. says. mark suffman from the University of Wisconsin was not involved in the experiment.

jennifer strobley Quantinuum said the team’s hardware is well-suited for new experiments because it provides advanced control over qubits and quantum computers have already achieved some of the lowest error rates ever. .

In 2023, a team of Harvard University researchers and their colleagues, including members of the quantum computing startup QuEra, broke the record for the largest number of logical qubits at once, 48. This is much more than his four logical qubits in the new device. But Strabley said the new device requires fewer physical qubits for each logical qubit, and the logical qubits have fewer errors than the one built by the Harvard team. “We used significantly fewer physical qubits and got better results,” she says.

However, some experts new scientist Without details about the experiment, researchers were not yet ready to qualify this new research as a breakthrough in quantum error correction.

It is generally believed that only quantum computers with more than 100 logical qubits can actually tackle scientifically and socially relevant problems in fields such as chemistry and materials science. The next challenge is to make everything bigger. Strabley and Svore say they are confident that the long-standing collaboration between Microsoft and Quantinuum will soon come to fruition.

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Source: www.newscientist.com

Microsoft’s quantum computer could be the most dependable yet

Posted on April 3, 2024 by Igor Mitreski

Quantinuum H2 chip

Quantinum

“What we did here gave me goosebumps. We showed that error correction is reproducible, works, and is reliable.” Krista Svoir At Microsoft.

jennifer strobley Quantinuum said the team's hardware is well-suited for new experiments because it provides advanced control over qubits and quantum computers have already achieved some of the lowest error rates ever. .

However, some experts new scientist Without details about the experiment, researchers were not yet ready to qualify this new research as a breakthrough in quantum error correction.

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Source: www.newscientist.com

Physicists are delving into quantum gravity using the concept of gravitational rainbows

Posted on March 26, 2024 by Igor Mitreski

The fans roar to life, pumping air upwards at 260 kilometers per hour. Wearing a baggy blue jumpsuit, red helmet, and plastic goggles, claudia de rum When you step into the glass room… Whoosh! Suddenly, she was suspended in the air, her wide grin on her face excited by her simulated experience of free fall.

I persuaded de Lamme, a theoretical physicist at Imperial College London, to go indoor skydiving with me at iFLY London. It seemed appropriate, given that much of her life has been dedicated to exploring the limits and true nature of gravity. At least on this occasion, jumping out of the plane wasn't an option for her.

As she explains in her new book, the beauty of falling, de Rum trained to be a pilot and then an astronaut, but medical problems ruined his chance for the ultimate escape from gravity. But as a theorist, she continued to delve deeper into this most familiar and mysterious force, making her mark by asking her fundamental question: “What is the weight of gravity?” Ta.

That means she is a graviton, a hypothetical particle that is thought to carry this force. If it had mass, as de Rum suspects, that would open a new window on gravity. Among other things, we may finally discover a “gravitational rainbow” that betrays the existence of gravitons. Along with gravitons, it will also become possible to provide a quantum description of gravity, which has been sought for many years.

When De Rum is suspended in the air, she makes it look easy. She will ascend soon…

Source: www.newscientist.com

Exploring the mysteries of black holes using a ‘Quantum tornado’

Posted on March 21, 2024 by Igor Mitreski

If you think a regular tornado is scary, fasten your seatbelts. Scientists have created a tornado so powerful that it resembles a black hole. why? This giant vortex closely mimics a black hole, so it could offer great potential for black hole research.

It was published in the magazine Nature experimental study We created something never seen before: a quantum tornado. Basically, while a normal tornado circulates by tearing apart trees and houses, a quantum tornado circulates atoms and particles.

To make the tornado mimic a black hole, the researchers needed to use helium in a “superfluid” state, meaning it has a low viscosity and can flow without resistance. These properties allow scientists to closely observe how helium interacts with its surroundings.

This led to the discovery that small waves on the liquid surface simulate the gravitational conditions around a rotating black hole.

So how did they do it? First, the team led by the University of Nottingham needed to achieve the right properties for the liquid. This involved cooling several liters of superfluid helium to the lowest possible temperature, below -271°C.

Normally, tiny objects called “quantum vortices” in liquid helium spread apart from each other. But at this new, ultra-low temperature, liquid helium takes on quantum properties and stabilizes.

Helium “quantum tornado” experimental equipment at the black hole laboratory. – Photo credit: Leonardo Solidoro

Using a new cryogenic device, researchers were able to trap tens of thousands of these tiny objects, creating a “vortex” similar to a tornado.

The success of this experiment will allow researchers to compare the interactions inside a simulated black hole with their own theoretical projections, giving scientists a new way to simulate theories of curved spacetime and gravity. Possibilities will be unlocked.

“When we first observed clear signs of black hole physics in our first analog experiments in 2017, it was a discovery of some strange phenomena that are often difficult, if not impossible, to study in other ways.” It was a breakthrough moment for understanding the phenomenon.” Professor Silke Weinfurtneris leading the research at the Black Hole Institute, where this experiment was developed.

“Now, with more sophisticated experiments, we have taken this research to the next level. This may lead to predictions of what will happen.”

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Source: www.sciencefocus.com

Google and XPRIZE collaboratively introduce $5 million reward to identify practical uses for quantum computers

Posted on March 4, 2024 by Igor Mitreski

Can quantum computers help?

Eric Lucero/Google

Google and XPRIZE are launching a $5 million competition to create a quantum computer that could actually benefit society. It’s already known that quantum computers can perform certain tasks faster than classical computers, ever since Google first claimed the quantum benefits of its Sycamore processor in 2019. However, these demonstration tasks are simple benchmarks and have no real-world applications.

“There are a lot of fairly abstract mathematical problems for which quantum computers can prove to provide very significant speedups,” he says. Ryan Babush Google. “However, much of the research community is less focused on adapting more abstract quantum acceleration to concrete real-world applications, or on trying to figure out how quantum computers can be used. I didn’t.”

To this end, Google and the XPRIZE Foundation are inviting researchers to come up with new quantum algorithms as part of a three-year competition. The winning algorithm could potentially solve an existing problem, such as finding a new battery electrolyte that significantly increases storage capacity, but it doesn’t have to actually solve the problem, Babush said. Instead, researchers only need to demonstrate how the algorithm is applied and detail the exact specifications of the quantum computing required. Alternatively, competitors could demonstrate how existing quantum algorithms can be applied to real-world problems that have not been considered before.

The award examines how big an impact an entrant’s algorithm can have, whether it tackles problems similar to those outlined in the United Nations’ Sustainable Development Goals, and how well it can be done on available machines. They will be judged on a variety of criteria, including feasibility. Now or in the near future.

The $5 million prize pool consists of a $3 million grand prize to be split between up to three winners, $1 million to five runners-up, and $50,000 each to the 20 semi-finalists. .

The award could help shift the focus of quantum computing researchers from technical definitions of quantum benefits, such as those demonstrated by Google and IBM, to real-world applications, it said. Nicholas Quesada At the Polytechnic University of Montreal, Canada. “[The prize is] “We realized clearly that this is a very important issue,” Quesada said. “We need to think about what we’re going to do with quantum computers.”

But finding socially beneficial quantum algorithms requires a deeper understanding of how quantum computers work, including how they deal with noise and errors, he said. bill fefferman at the University of Chicago. The award does not address this fundamental aspect of building quantum computers, he says.

“I’m generally very optimistic that we’ll find an algorithm that’s really useful,” Pfefferman says. “I’m not very optimistic that within the next three years we’ll be able to discover those algorithms and implement them on the current hardware that’s going to exist.”

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Source: www.newscientist.com

Groundbreaking Discovery in Quantum Gravity May Lead to a Unified “Theory of Everything”

Posted on February 24, 2024 by Igor Mitreski

Curious about what goes on inside a black hole? Wondering about the origins of the Big Bang and how the forces of the universe came together? These are some of the biggest questions humanity has about the universe, and new discoveries are bringing us closer to the answers than ever before.

Scientists have made a breakthrough in measuring gravity in the quantum world, with British, Dutch, and Italian teams utilizing new technology to detect weak gravity on small particles. By suspending particles weighing just 0.43 mg at ultra-low temperatures, they were able to isolate the vibrations of the particles using magnets and superconducting devices.

This groundbreaking technique allowed scientists to measure weak attractive forces of only 30 attonewtons (aN), a force smaller than that of a bacterium on a table’s surface. Previously, understanding how gravity worked at the microscopic level had eluded scientists, but this discovery has shed light on the interaction of forces with particles at a small scale.

Lead author of the study, Tim Hooks from the University of Southampton, noted that scientists have been struggling for a century to understand how gravity and quantum mechanics interact. This new discovery brings us closer to unraveling the mysteries of the universe and potentially paves the way for further advancements in measuring quantum gravity.

By continuing to refine the method used in this study, researchers hope to delve deeper into the forces that govern the universe, ultimately leading to a better understanding of the very structure of our cosmos.

“We are on the brink of new discoveries about gravity and the quantum world,” said Professor Hendrik Ulbricht, one of the study authors.

For more information, visit Professor Hendrik Ulbricht’s profile.

Source: www.sciencefocus.com

Using small magnets to measure gravity at a quantum level

Posted on February 24, 2024 by Igor Mitreski

All objects, no matter how small, exert gravity.

Karl Drenck/BeholdingEye/Getty Images

A device that can measure the force of gravity on particles lighter than a single grain of pollen could help us understand how gravity works in the quantum world.

Despite being stuck to the ground, gravity is the weakest force known to us. Only very large objects, such as planets and stars, generate enough gravity to be easily measured. Doing the same for a very small object at a fraction of the distance and mass in the quantum realm is also possible because the size of the force is so small, but a nearby larger object could overwhelm the signal. It is very difficult because there is

now hendrik ulbricht and colleagues at the University of Southampton in the UK have developed a new way to measure gravity on a small scale, using tiny neodymium magnets weighing about 0.5 milligrams that are suspended in a magnetic field that opposes Earth's gravity.

Small changes in the magnetic field of a magnet caused by the gravitational influence of nearby objects can be converted into a measure of gravity. The whole thing is cooled to near absolute zero and suspended on a spring system to minimize external forces.

This probe can measure the gravitational pull of objects weighing just a few micrograms. “We can increase the sensitivity and push the study of gravity into a new regime,” Ulbricht says.

He and his team found that a 1-kilogram test mass rotating nearby could measure a force of 30 atton-Newtons on a particle. An atnewton is one billionth of a newton. One limitation is that the test mass must be moving at a suitable velocity to cause gravitational resonance with the magnet. Otherwise, it will not be strong enough to pick up the force.

The next stage of the experiment will reduce the test mass to the same size as the magnetic particles so that gravity can be tested while the particles exhibit quantum effects such as entanglement and superposition. Ulbricht said this would be difficult because with such a small mass, all other parts of the experiment would need to be incredibly precise, such as the exact distance between the two particles. Masu. It may take at least 10 years to reach this stage.

“The fact that they even attempted this measurement is appalling to me,” he says. julian starlingis a UK-based engineer, as it is difficult to separate other gravitational effects from the exploration mass. Professor Starling said that in this experiment, the anti-vibration system appeared to have had a small but significant effect on airborne particles, so researchers need to find ways to minimize the gravitational effects of the anti-vibration system. It states that there is.

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Source: www.newscientist.com

Is it Possible that Quantum Clues in the Brain could Resurrect a Core Theory of Consciousness?

Posted on January 19, 2024 by Igor Mitreski

Two weeks before the pandemic lockdown in March 2020, I flew to Tucson, Arizona, and knocked on the door of a suburban ranch-style home. I was there to visit Stuart Hammeroff. He is an anesthesiologist and co-inventor with Nobel Prize-winning physicist Roger Penrose of a radical proposal for how conscious experience arises: that it has its origins in quantum phenomena in the brain.

Such ideas, in one form or another, have existed on the fringes of mainstream consciousness research for decades. There is no solid experimental evidence that quantum effects occur in the brain, as critics claim, and aside from a clear idea of how quantum effects produce consciousness, they come in from the cold. Not that it was. “It was very popular to bash us,” Hammeroff told me.

But after a week of questioning him about the concept, I realized that at least his version of quantum consciousness is widely misunderstood. Partly, I think it’s Hammeroff’s fault. He gives the impression of a single package. In fact, his ideas are a series of independent proposals, each forcing us to confront important questions about the relationship between fundamental physics, biology, and the indescribable thing called consciousness. I am.

Furthermore, during my visit I saw several experiments that Hammeroff had proposed come to fruition, and it became clear that his ideas could be applied to experimental research. Researchers have now provided preliminary evidence suggesting that fragile quantum states can persist in the brain and that anesthetics can influence those states.

Now is the time to start taking it…

Source: www.newscientist.com

Rethinking Quantum Consciousness: An Intriguing Experiment

Posted on January 17, 2024 by Igor Mitreski

Two weeks before the pandemic lockdown in March 2020, I flew to Tucson, Arizona, and knocked on the door of a suburban ranch-style home. I was there to visit Stuart Hameroff. He is an anesthesiologist and co-inventor with Nobel Prize-winning physicist Roger Penrose of a radical proposal for how conscious experience arises: that the origins of conscious experience lie in quantum phenomena in the brain.

But after a week of questioning him about the concept, I realized that at least his version of quantum consciousness is widely misunderstood. Partly, I think it’s Hameroff’s fault. He gives the impression of a single package. In fact, his ideas are a series of independent proposals, each forcing us to confront important questions about the relationship between fundamental physics, biology, and the indescribable thing called consciousness.

Furthermore, during my visit I saw several experiments that Hameroff had proposed come to fruition, and it became clear that his ideas could be applied to experimental research. Researchers have now provided preliminary evidence suggesting that fragile quantum states can persist in the brain and that anesthetics can influence those states.

Now is the time to start taking it…

Source: www.newscientist.com

Researchers Develop Large Quantum Vortex to Replicate Black Hole Properties

Posted on January 17, 2024 by Igor Mitreski

Researchers created tornado-like vortices in superfluid helium

Yoshigin/Shutterstock

Giant quantum vortices could allow researchers to study black holes. This vortex is a special form of liquid helium vortex that exhibits quantum effects. The result has some properties similar to a black hole and acts as a kind of simulator.

In the region around a black hole, the laws of gravity and quantum mechanics interact, producing effects that cannot be observed elsewhere in the universe. This makes these regions particularly important to study. “There are interesting physics happening around black holes, but many of them are out of our reach,” he says. Silke Weinfurtner at the University of Nottingham, UK. “Thus, we can use these quantum simulators to investigate phenomena that occur around black holes.”

To build the quantum simulator, Weinfurtner and his colleagues used superfluid helium, which flows at a very low viscosity, 500 times lower than water. Because it moves without friction, this form of helium exhibits unusual quantum effects and is known as a quantum fluid. The researchers filled a tank with helium with a rotating propeller at the bottom. As the propeller rotated, a tornado-like vortex was generated in the fluid.

“Similar vortices have been created in physical systems other than superfluid helium, but their strength is generally at least several orders of magnitude weaker,” he says. Patrick Svanchara, is also enrolled at the University of Nottingham and is part of the team. The strength and size of the vortex are critical to producing an interaction significant enough to observe between the vortex and the remaining fluid in the tank.

The vortices in this work were a few millimeters in diameter, much larger than other stable vortices created to date. quantum fluid In the past. In quantum liquids, rotation only occurs in tiny “packets” called quanta, which are essentially tiny vortices, so creating such large vortices is difficult. Many of them tend to become unstable when clustered, but the experimental setup here allows the researchers to combine about 40,000 rotating quanta to form what is called a giant quantum vortex. It's done.

“This is an experimental masterpiece,” he says Jeff Steinhauer He received his PhD from the Technion-Israel Institute of Technology, a pioneer in laboratory simulations of black holes. “They took a very well-established, old, classic technology called superfluid helium and did something really new with it, significantly increasing their technical capabilities compared to what had been done in the past. .”

The researchers observed how small waves in the fluid interacted with vortices. This process mimics the way the universe's cosmic field interacts with a rotating black hole. They discovered hints of a black hole phenomenon called ringdown mode. This phenomenon occurs after two black holes combine and the resulting single black hole is shaken by the residual energy of the combination.

Now that it has been established that this type of vortex exhibits behavior similar to that seen in black holes, researchers plan to use quantum vortices to study more elusive phenomena. “This is an excellent starting point for investigating some black hole physics processes, seeking new insights and potentially discovering hidden treasures along the way,” Weinfurtner says. .

topic:

Source: www.newscientist.com

Harvard University debuts the world’s first logical quantum processor

Posted on December 25, 2023 by Igor Mitreski

Researchers at Harvard University have achieved a significant milestone in quantum computing by developing a programmable logic quantum processor that can encode 48 logic qubits and perform hundreds of logic gate operations. Hailed as a potential turning point in the field, this advance marks the first demonstration of large-scale algorithm execution on an error-correcting quantum computer.

Harvard University’s breakthrough quantum computing features a new logical quantum processor with 48 logical qubits, enabling the execution of large-scale algorithms on error-corrected systems. The development, led by Mikhail Lukin, represents a major advance towards practical fault-tolerant quantum computers.

In quantum computing, a quantum bit or “qubit” is a unit of information, similar to a binary bit in classical computing. For more than two decades, physicists and engineers have shown the world that quantum computing is possible in principle by manipulating quantum particles such as atoms, ions, and photons to create physical qubits. I did.

But exploiting the strangeness of quantum mechanics for calculations is more complicated than collecting enough physical qubits, which are inherently unstable and prone to collapsing from their quantum states.

Logical qubit: the building block of quantum computing

The real coin of the realm in useful quantum computing are so-called logical qubits. This is a bunch of redundant, error-corrected physical qubits that can store information for use in quantum algorithms. Creating logical qubits as controllable units like classical bits is a fundamental hurdle for the field, and until quantum computers can reliably run on logical qubits, , it is generally accepted that the technology cannot really take off. To date, the best computing systems have demonstrated either: two logical qubits and one quantum gate operation – similar to just one operation code unit – between them.

A team led by quantum expert Mikhail Lukin (right) has achieved a breakthrough in quantum computing. Dr. Dorev Brufstein was a student in Lukin’s lab and the lead author of the paper.

Credit: Jon Chase/Harvard University Staff Photographer

Breakthrough in quantum computing at Harvard University

A team from Harvard University led by co-director Mikhail Lukin, Joshua and Beth Friedman Professor of Physics. Harvard Quantum Initiative has achieved an important milestone in the quest for stable and scalable quantum computing. For the first time, the team has created a programmable logic quantum processor that can encode up to 48 logic qubits and perform hundreds of logic gate operations. Their system is the first demonstration of large-scale algorithm execution on an error-corrected quantum computer, and heralds the early days of fault-tolerant, or guaranteed uninterruptible, quantum computing.

was announced on Nature, this research was conducted in collaboration with Marcus Greiner, the George Basmer Leverett Professor of Physics.colleague from Massachusetts Institute of Technology; and based in Boston QuEra Computing, a company founded on technology from Harvard University’s research labs.

Harvard University’s Office of Technology Development recently entered into a licensing agreement with QuEra for a patent portfolio based on innovations developed at the Lukin Group.

Lukin called the achievement a potential inflection point similar to the early days of the field of artificial intelligence, where long-theorized ideas of quantum error correction and fault tolerance are beginning to come to fruition.

“I think this is one of those moments where it’s clear that something very special is going to happen,” Lukin said. “While there are still challenges ahead, we expect this new advance to greatly accelerate progress toward large-scale, useful quantum computers.”

This breakthrough is based on several years of research into “quantum computing architectures.” neutral atomic arrangement, pioneered in Lukin’s lab and now commercialized by QuEra. The main component of the system is a block of ultracold, suspended rubidium atoms in which the atoms (the system’s physical qubits) move around and connect, or “entangle”, into pairs during calculations. Entangled pairs of atoms form gates, units of computational power.

Previously, the team demonstrated Low error rate for entanglement operations proving the credibility of their neutrality atom array system.

Impact and future directions

“This breakthrough is a masterpiece of quantum engineering and quantum design,” said Dennis Caldwell, acting deputy director of the National Science Foundation’s Mathematics and Physical Sciences Directorate, which supported the research through NSF’s Physics Frontiers Center and Quantum Leap Challenge Institute programs. says. “By using neutral atoms, the team has not only accelerated the development of quantum information processing, but also opened new doors to the search for large-scale logical qubit devices that could have transformative benefits for science and society as a whole. I opened the door.

Researchers are now using logic quantum processors to demonstrate parallel multiplexed control of entire patches of logic qubits using lasers. This result is more efficient and scalable than controlling individual physical qubits.

“We are seeking to mark a transition in the field by starting to test algorithms that use error-corrected qubits instead of physical qubits, enabling a path to larger devices. ,” said lead author Dorev Brubstein of the Griffin School of Arts and Sciences student in Lukin’s lab.

The team continues to work on demonstrating more types of operations with 48 logical qubits and configuring the system to run continuously, as opposed to manual cycles as it currently does.

Reference: “Logical quantum processors based on reconfigurable atomic arrays” Dolev Bluvstein, Simon J. Evered, Alexandra A. Geim, Sophie H. Li, Hengyun Zhou, Tom Manovitz, Sepehr Ebadi, Madelyn Cain, Marcin Kalinowski, Dominik Hangleiter, J. Pablo Bonilla Ataydes, Nishad Mascara, Iris Kong, Xun Gao, Pedro Salles Rodríguez, Tomas Karoliszyn, Julia Semeghini, Michael J. Galans, Markus Greiner, Vladan Vretić, Mikhail D. Lukin, December 6, 2023, Nature.
DOI: 10.1038/s41586-023-06927-3

This research was supported by the Defense Advanced Research Projects Agency through the Noisy Medium-Scale Quantum Devices Optimization Program. The Ultracold Atom Center, a National Science Foundation Physics Frontier Center. Army Research Office. and QuEra computing.

Source: scitechdaily.com

New approach uncovers the complete chemical complexity of quantum decoherence

Posted on December 22, 2023 by Igor Mitreski

Rochester researchers have reported a strategy for understanding how molecules in completely chemically complex solvents lose their quantum coherence. This discovery opens the door to rational tuning of quantum coherence through chemical design and functionalization.

Credit: Annie Ostau de Lafon

This discovery can be used to design molecules with custom quantum coherence properties, laying the chemical basis for new quantum technologies.

In quantum mechanics, particles can exist in multiple states at the same time, which defies the logic of everyday experience. This property, known as quantum superposition, is the basis for new quantum technologies that promise to transform computing, communications, and sensing. However, quantum superposition faces a serious challenge: quantum decoherence. During this process, interaction with the surrounding environment disrupts the delicate superposition of quantum states.

Quantum decoherence challenges

To unlock the power of chemistry and build complex molecular architectures for practical quantum applications, scientists need to understand and control quantum decoherence so they can engineer molecules with specific quantum coherence properties. must be. To do so, we need to know how to rationally modify the chemical structure of molecules to modulate or alleviate quantum decoherence. To do this, scientists need to know the “spectral density,” a quantity that summarizes the speed at which the environment moves and the strength of its interactions with the quantum system.

A breakthrough in spectral density measurement

Until now, quantifying this spectral density in a way that accurately reflects molecular complexity has remained difficult in theory and experiment. However, a team of scientists has developed a way to extract the spectral density of molecules in a solvent using a simple resonance Raman experiment, a method that fully captures the complexity of the chemical environment.

A team led by Ignacio Franco, an associate professor of chemistry and physics at the University of Rochester, published their findings in Proceedings of the National Academy of Sciences.

Relationship between molecular structure and quantum decoherence

Using the extracted spectral density, we can not only understand how quickly decoherence occurs, but also determine which parts of the chemical environment are primarily responsible for decoherence. As a result, scientists can now map decoherence pathways and link molecular structure to quantum decoherence.

“Chemistry is built on the idea that molecular structure determines the chemical and physical properties of matter. This principle guides the modern design of molecules for medical, agricultural, and energy applications.” Using our strategy, we can finally begin to develop chemical design principles for emerging quantum technologies,” said Ignacio Gustin, a chemistry graduate student at the University of Rochester and lead author of the study.

Resonant Raman experiments: an important tool

The breakthrough came when the team realized that resonance Raman experiments provided all the information needed to study decoherence in its full chemical complexity. Although such experiments are routinely used to study photophysics and photochemistry, their usefulness for quantum decoherence had not been evaluated. The key insight was shared by David McCamant, an associate professor in the Department of Chemistry at the University of Rochester and an expert in Raman spectroscopy, and Jang Woo Kim, currently on the faculty at Chonnam National University in South Korea and an expert in quantum decoherence. This became clear from the discussion. He was a postdoctoral fellow at the University of Rochester.

Case study: Thymine decoherence

The researchers used their method to show for the first time how the superposition of electrons in thymine, one of the building blocks of humans, occurs. DNA, it takes only 30 femtoseconds (one femtosecond is one billionth of a billionth of a second) after absorbing ultraviolet light. They found that some vibrations within the molecule were dominant in the early stages of the decoherence process, while the solvent was dominant in the later stages. Furthermore, they found that chemical modifications to thymine significantly altered the decoherence rate, with hydrogen bonding interactions near the thymine ring resulting in more rapid decoherence.

Future implications and applications

Ultimately, the team’s research paves the way to understanding the chemical principles governing quantum decoherence. “We are excited to use this strategy to finally understand quantum decoherence in molecules of full chemical complexity and use it to develop molecules with robust coherence properties.” Franco said.

Reference: “Mapping the intramolecular electron decoherence pathway” by Ignacio Gustin, Chan Woo Kim, David W. McCamant, and Ignacio Franco, November 28, 2023. Proceedings of the National Academy of Sciences. DOI: 10.1073/pnas.2309987120

Source: scitechdaily.com

Quantum Batteries: Revolutionizing Power Source Technology

Posted on December 22, 2023 by Igor Mitreski

Quantum batteries, with their innovative charging methods, are a revolutionary development in battery technology and offer potential for greater efficiency and a broader range of uses in sustainable energy solutions. These batteries use quantum phenomena to capture, distribute, and store power, surpassing the capabilities of traditional chemical batteries in certain low-power applications. A counterintuitive quantum process known as “indefinite causal order” is being used to improve the performance of these quantum batteries, bringing this futuristic technology closer to reality.

Despite being mostly limited to laboratory experiments, researchers are working on various aspects of quantum batteries with the hope of integrating them into practical applications in the future. Researchers, including Chen Yuanbo and associate professor Yoshihiko Hasegawa from the University of Tokyo, are focusing on finding the best way to charge quantum batteries in the most efficient manner.

Using a new quantum effect called “indefinite causal order,” the research team has found that charging quantum batteries can have a significant impact on their performance. This effect has also led to a surprising reversal of the relationship between charger power and battery charging, enabling higher energy batteries to be charged using significantly less electricity. Furthermore, the fundamental principles uncovered through this research have the potential to improve performance in various thermodynamics and heat transfer processes, such as solar panels.

The research paper, titled “Charging Quantum Batteries with Undefined Causal Order: Theory and Experiments,” provides further details on this groundbreaking work and its potential applications in sustainable energy solutions.

Source: scitechdaily.com

New experiment challenges the principles of quantum electrodynamics

Posted on December 20, 2023 by Igor Mitreski

The X-ray beam from Europe’s XFEL, the world’s largest X-ray laser, can only be seen with photographic clarity in complete darkness and with an exposure time of 90 seconds. In 2024, the first experiment to detect quantum fluctuations in vacuum will take place here. Credit: European XFEL / Jan Hosan

The HZDR team proposes improvements to experiments aimed at probing the limits of physics.

Completely empty – that’s how most of us imagine a vacuum. But in reality, it is filled with flickers of energy, or quantum fluctuations. Scientists are now preparing laser experiments aimed at examining these vacuum fluctuations in new ways, which could provide clues to new laws of physics.

The Dresden-Rossendorf-Helmholtzzentrum (HZDR) research team has developed a series of suggestions designed to make experiments more effective and increase the chances of success.The research team will publish their findings in a scientific journal Physical Review D.

The world of physics has long recognized that the vacuum is not completely hollow, but filled with vacuum fluctuations, eerie quanta that flicker around in time and space. Although it cannot be captured directly, its effects can be observed indirectly, for example through changes in the electromagnetic field of small particles.

However, it is still not possible to verify vacuum fluctuations without the presence of particles. If this can be achieved, one of the fundamental theories of physics, quantum electrodynamics (QED), will be proven in a previously untested area. However, if such experiments reveal deviations from theory, it would suggest the existence of new, previously undiscovered particles.

Dr. Ulf Zastrau heads the HED (High Energy Density Science) experimental station at European XFEL. HED Beam In his chamber, flashes from his X-ray laser, the world’s largest, must be matched with light pulses from his ReLaX high-power laser operated by HZDR to detect vacuum fluctuations. Credit: European XFEL / Jan Hosan

Experiments to achieve this are planned as part of the Helmholtz International Extreme Field Beamline (HIBEF), a research consortium led by HZDR, at the HED experimental station of the world’s largest X-ray laser, the European XFEL, in Hamburg. There is. . The basic principle is that an ultra-powerful laser fires short, powerful flashes into a vacuumed stainless steel chamber. The aim is to manipulate vacuum fluctuations to, as if by magic, change the polarization of his X-ray flashes from his XFEL in Europe, i.e. rotate their direction of vibration.

“It’s like sliding a clear plastic ruler between two polarizing filters and bending it back and forth,” explains HZDR theorist Professor Ralf Schutzhold. “A filter is originally set up to prevent light from passing through it. Bending the ruler changes the direction of the vibrations of light, allowing you to see something.” In this analogy, the ruler responds to fluctuations in the vacuum. and a super powerful laser flash bends the vacuum fluctuations.

Two flashes instead of just one

The original concept involved firing a single optical laser flash into a chamber and using special measurement techniques to record whether the polarization of the X-ray flash changed. But there’s a problem. “The signal can be very weak,” Schutzhold explains. “Only one in a trillion X-ray photons can change its polarization.”

However, this may be below current measurement limits, and events may simply slip through the cracks undetected. Schutzhold and his team therefore rely on a variation of firing not just one but two of his light laser pulses into a vacuum chamber simultaneously.

Both flashes run into it and literally collide. Her X-ray pulses from Europe’s XFEL are set to hit precisely the point of impact. The clincher: Laser flash collisions affect her X-ray pulses like a kind of crystal. Just as X-rays are diffracted, or deflected, when they pass through natural crystals, XFEL X-ray pulses are deflected by the brief “crystal of light” of the two colliding laser flashes.

“This not only changes the polarization of the X-ray pulse, but also slightly deflects the pulse,” explains Ralf Schutzholt. The researchers hope that this combination may improve the chances of actually measuring effects. The researchers calculated different options for the firing angle of the two laser flashes colliding inside the chamber. Experimentation will tell you which variant works best.

Are you targeting ultralight ghost particles?

The visibility could also be further improved if the two laser flashes fired into the chamber were not the same color, but two different wavelengths. This also allows for small changes in the energy of the X-ray flash, which is useful for measuring effectiveness as well. “However, this is technically very difficult and may be implemented at a later date,” Schutzhold says.

The project is currently in the planning stage in collaboration with the European XFEL team at the HED experimental station in Hamburg, with first trials scheduled to begin in 2024. If successful, QED could be confirmed again.

However, perhaps experiments will reveal deviations from established theory. This could be caused by previously undiscovered particles, such as ultralight ghost particles known as axions. “And it will clearly demonstrate additional laws of nature that were previously unknown,” Schutzholt says.

Reference: “Quantum vacuum diffraction and birefringence detection scheme” N. Ahmadiniaz, TE Cowan, J. Grenzer, S. Franchino-Viñas, A. Laso Garcia, M. Šmíd, T. Toncian, MA Trejo, R. Schützhold , October 10, 2023 Physical Review D.
DOI: 10.1103/PhysRevD.108.076005

Source: scitechdaily.com

Caltech Researchers Introduce Novel Error-Correction Technique for Quantum Computers

Posted on December 16, 2023 by Igor Mitreski

Researchers at the California Institute of Technology have developed a quantum erasure device to correct “erasure” errors in quantum computing systems. The technique allows fluorescent error detection and correction by manipulating alkaline earth neutral atoms with laser light “tweezers.” This innovation leads to a 10-fold increase in the entanglement rate of Rydberg neutral atomic systems, and is an important step forward in making quantum computers more reliable and scalable.

For the first time, researchers have successfully demonstrated the identification and removal of “erasure” errors.

Future quantum computers are expected to revolutionize problem-solving in a variety of fields, including creating sustainable materials, developing new drugs, and solving complex problems in fundamental physics. However, these pioneering quantum systems are more error-prone than the classical computers we use today. Wouldn’t it be great if researchers could whip out a special quantum eraser and remove mistakes?

Report in magazine Nature, A group of researchers led by the California Institute of Technology has demonstrated for the first time a type of quantum erasure device. Physicists have shown that mistakes can be pinpointed and corrected. quantum computing A system known as an “erasure” error.

“Typically, it’s very difficult to detect errors in quantum computers, because just the act of looking for errors creates more errors,” said Manuel Endres, co-lead author of the new study and co-author of the study. says Adam Shaw, a graduate student in the room. Professor of Physics at California Institute of Technology. “However, we found that with careful control, certain errors can be precisely identified and erased without significant impact. This is where the name erasure comes from.”

How quantum computing works

Quantum computers are based on the physical laws that govern the subatomic realm, such as entanglement, a phenomenon in which particles mimic each other while remaining connected without direct contact. In the new study, researchers focused on a type of quantum computing platform that uses arrays of neutral atoms, or atoms that carry no electric charge. Specifically, they manipulated individual alkaline earth neutral atoms trapped inside “tweezers” made with laser light. The atoms are excited to a high-energy state, or “Rydberg” state, and neighboring atoms begin to interact.

Errors are typically difficult to spot in quantum devices, but researchers have shown that if carefully controlled, some errors can cause atoms to emit light. The researchers used this ability to perform quantum simulations using atomic arrays and laser beams, as shown in this artist’s concept. Experiments show that quantum simulations can be run more efficiently by discarding erroneous atoms that are glowing.Credit: Caltech/Lance Hayashida

“The atoms in our quantum systems interact with each other and generate entanglements,” said the study’s other co-lead author, a former postdoctoral fellow at the California Institute of Technology and now at a French quantum computing company. Pascal Scholl, who works at PASQAL, explains.

Entanglement is what allows quantum computers to outperform classical computers. “But nature doesn’t like to stay in this entangled state,” Scholl explains. “Eventually an error will occur and the entire quantum state will be destroyed. You can think of these entangled states like a basket full of apples, where the atoms are the apples. Over time , some apples will start to rot. If you don’t remove these apples from the basket and replace them with fresh apples, all the apples will quickly rot. It’s not clear how to completely prevent these errors from occurring. Therefore, the only viable option at this time is to detect and remediate them.”

Innovation in error detection and correction

The new error-trapping system is designed so that atoms with errors fluoresce, or glow, when hit by a laser. “We have images of glowing atoms that show us where the errors are, so we can either exclude them from the final statistics or actively correct them by applying additional laser pulses.” says Scholl.

Implementation theory of erasure detection in neutral atom The system was first developed by Jeff Thompson, a professor of electrical and computer engineering. princeton university, and his colleagues.The team recently reported a demonstration of the technique in the journal Nature.

The Caltech team says that by removing and identifying errors in the Rydberg atomic system, the overall rate of entanglement, and therefore fidelity, can be improved. In the new study, the researchers report that only one out of every 1,000 pairs of atoms failed to entangle. This is a 10-fold improvement over what was previously achieved and the highest entanglement rate ever observed for this type of system.

Ultimately, these results bode well for quantum computing platforms that use Rydberg neutral atomic arrays. “Neutral atoms are the most scalable type of quantum computer, but until now they have not had the high degree of entanglement fidelity,” Shaw says.

References: “Elimination Transformations in High-Fidelity Rydberg Quantum Simulators” Pascal Scholl, Adam L. Shaw, Richard Bing-Shiun Tsai, Ran Finkelstein, Joonhee Choi, Manuel Endres, October 11, 2023. Nature.
DOI: 10.1038/s41586-023-06516-4

The research was funded by the National Science Foundation (NSF) through the Institute for Quantum Information and Materials (IQIM), based at the California Institute of Technology. Defense Advanced Research Projects Agency. NSF Career Award. Air Force Office of Scientific Research. NSF Quantum Leap Challenge Laboratory. Department of Energy’s Quantum Systems Accelerator. Fellowships in Taiwan and California Institute of Technology. and a Troesch Postdoctoral Fellowship. Other Caltech-related authors include graduate student Richard Bing-Shiun Tsai;Ran Finkelstein, Troesch Postdoctoral Research Fellow in Physics. Former postdoc Joonhee Choi is now a professor at Stanford University.

Source: scitechdaily.com

Can Lentils Transmit Secret Quantum Messages Through Biophotons?

Posted on December 15, 2023 by Igor Mitreski

In the hills south of Rome is Italy’s premier nuclear physics laboratory, the Frascati National Laboratory. It has all the equipment you’d expect from a state-of-the-art scientific facility, including giant magnets, powerful particle accelerators, and exposed electrical wires strung throughout. Many of the researchers here are trying to unlock the secrets of the Standard Model, the best theory of how reality works at the most fundamental level. And then there’s the room where Catalina Cruceanu is keeping watch over a small box of lentils.

Admittedly, this is not at all normal behavior for a physicist, but Cruceanu explains why the equipment and methods of nuclear physics cause lentils and other organisms to constantly emit extremely weak photons and particles. We hope to solve the 100-year-old mystery. light’s. Some people think that these “biophotons” are not important. Others argue that they are a subtle form of lentil communication. Cruceanu leans towards the latter position, and even has a hunch that the pulses between pulses may contain secret quantum signals. “These are just the first steps, but it looks like it’s going to be very interesting,” she says.

There are already hints that living things exploit quantum phenomena, and there is also inconclusive evidence that quantum phenomena have features in things like photosynthesis and the way birds move. But lentils may be the most surprising example of quantum biology yet, because their complex behavior is poorly understood, he says. Michal Shifra At the Czech Academy of Sciences in Prague. “That would be great,” Shifra says. “If that’s true.” Because so many living things emit biophotons, such a discovery could indicate that quantum effects are ubiquitous…

Source: www.newscientist.com

Discovery of a ‘Quantum Switch’ Controlling Photosynthesis by Scientists

Posted on December 15, 2023 by Igor Mitreski

A new study reveals the quantum switching mechanism of light-harvesting complex II (LHCII), which is critical for efficient photosynthesis. This discovery, achieved through advanced cryo-EM and theoretical calculations, supports a dynamic role for LHCII in regulating energy transfer in plants. Credit: SciTechDaily.com

Photosynthesis is an important process that allows plants to use sunlight to convert carbon dioxide into organic compounds. Light-harvesting complex II (LHCII) consists of dye molecules bound to proteins. It alternates between two main roles. Under strong light, excess energy is dissipated as heat through non-photochemical quenching, and under weak light, light is efficiently transferred to the reaction center.

Recent bioengineering research has revealed that faster switching between these functions can improve photosynthetic efficiency. For example, soybean crops showed yield increases of up to 33%. However, the precise atomic-level structural changes in LHCII that cause this control have not been known until now.

The molecular mechanism of NPQ and acidity-induced changes in several key structural factors cause the LHCII trimer to switch between light-harvesting and energy-quenching states.Credit: Institute of Physics

innovative research approach

In the new study, researchers led by Professor Weng Yuxiang from the Institute of Physics, Chinese Academy of Sciences, in collaboration with Professor Gao Jiali’s group from the Shenzhen Bay Institute, combined single-particle cryo-electron microscopy (cryo-EM) research. Using multistate density functional theory (MSDFT) calculations of energy transfer between photosynthetic pigment molecules, we analyzed the dynamic structure of his LHCII at atomic resolution and identified photosynthetic pigment quantum switches for intermolecular energy transfer. Masu.

As part of the study, they developed a series of six cryogenic states, including energy transfer states with LHCII in solution and energy quenching states with laterally confined LHCII in membrane nanodisks under neutral and acidic conditions. reported the EM structure.

Comparing these different structures shows that LHCII undergoes a structural change upon acidification. This change allosterically changes the interpigment distance of the fluorescence quenching locus lutein 1 (Lut1)-chlorophyll 612 (Chl612) only when LHCII is confined to membrane nanodiscs, leading to the quenching of excited Chl612 by Lut1. cause. Therefore, lateral pressure-confined LHCII (e.g., aggregated LHCII) is a prerequisite for non-photochemical quenching (NPQ), whereas acidThe induced conformational change enhances fluorescence quenching.

Cryo-EM structures of LHCII in nanodiscs and surfactant solutions at pH 7.8 and 5.4. Credit: Institute of Physics

Quantum switching mechanism in photosynthesis

Through cryo-EM structures and MSDFT calculations of known crystal structures in the extinction state and transient fluorescence experiments, an important quantum switching mechanism of LHCII with the Lut1-Chl612 distance as a key factor was revealed.

This distance controls the energy transfer quantum channels in response to lateral pressure and conformational changes to LHCII. That is, a small change in the critical distance of 5.6 Å allows a reversible switch between light collection and excess energy dissipation. This mechanism allows for rapid response to changes in light intensity, achieving both high efficiency and efficiency. photosynthesis Balanced photoprotection using LHCII as a quantum switch.

Fluorescence decay rate, relationship of Lut1–Chl612 electronic bond strength to Lut1–Chl612 separation distance, and plot of Lut1–Chl612 distance versus crossing angle of TM helices A and B in different LHCII structures. Credit: Institute of Physics

Previously, these two research groups collaborated on molecular dynamics simulations and ultrafast infrared spectroscopy experiments to propose that LHCII is an allosterically controlled molecular machine. Their current experimental cryo-EM structure confirms previously theoretically predicted structural changes in his LHCII.

Reference: “Cryo-EM structure of LHCII in photoactive and photoprotected states reveals allosteric control of light harvesting and excess energy dissipation” Meixia Ruan, Hao Li, Ying Zhang, Ruoqi Zhao, Jun Zhang, Yingjie Wang , Jiali Gao, Zhuan Wang, Yumei Wang, Dapeng Sun, Wei Ding, Yuxiang Weng, August 31, 2023, natural plants.
DOI: 10.1038/s41477-023-01500-2

This research was supported by a project of the Chinese Academy of Sciences, the National Natural Science Foundation of China, and the Shenzhen Science and Technology Innovation Committee.

Source: scitechdaily.com

The merger of quantum biology and AI fueled genome editing advancements

Posted on November 11, 2023 by Igor Mitreski

Scientists at Oak Ridge National Laboratory have utilized quantum biology and explainable artificial intelligence to advance CRISPR Cas9 technology for genome editing in microorganisms. This breakthrough has enabled more precise genetic modification of microorganisms, opening up possibilities for the production of renewable fuels and chemicals. The research at Oak Ridge National Laboratory has significantly improved the efficiency of CRISPR Cas9 genome editing in microorganisms and contributed to renewable energy development.

CRISPR is a powerful tool for bioengineering, used to modify the genetic code to improve the performance of organisms or correct mutations. ORNL scientists developed a method to improve the accuracy of the CRISPR Cas9 gene editing tool used to modify microorganisms for the production of renewable fuels and chemicals. They have leveraged their expertise in quantum biology, artificial intelligence, and synthetic biology to achieve this.

To improve the modeling and design of guide RNAs, ORNL scientists sought to better understand what is happening at the most fundamental level in the cell nucleus, where genetic material is stored. They turned to quantum biology to study how electronic structure affects the chemical properties and interactions of nucleotides, such as DNA and RNA.

Furthermore, scientists at ORNL have built an explainable artificial intelligence model called iterated random forest, which has been used to train the model on a dataset of about 50,000 guide RNAs targeting the genome of Escherichia coli. This model has provided important features regarding the nucleotides that allow for better selection of guide RNAs.

Improving the CRISPR Cas9 model provides scientists with a high-throughput pipeline for linking genotype to phenotype in functional genomics. This research will impact efforts at the ORNL-led Center for Bioenergy Innovation (CBI), such as improving bioenergy feedstock plants and bacterial fermentation of biomass.

The results of this research significantly improve the prediction of guide RNAs. This represents an exciting advance toward understanding how avoid ‘mistakes’ and improving the ability to use CRISPR tools to predictively modify the DNA of more organisms. The study was funded by SEED SFA and CBI, part of the DOE Office of Science’s Biological and Environmental Research Program, ORNL’s Laboratory-Directed Research and Development Program, and OLCF and Compute’s High Performance Computing Resources and Data Environment for Science, both supported by the Office of Science.

Source: scitechdaily.com