Tag Archives: laser

Scientists Propose Installing a Super Laser on the Moon for Revolutionary Research

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Illustration of dark craters near the moon’s south pole

Explore the Dark Craters near the Moon’s South Pole

Credit: Science Photo Library / Alamy

Scientists aim to establish a groundbreaking laser system in one of the moon’s coldest craters to significantly enhance the navigation capabilities of lunar landers and rovers.

Ultra-stable lasers are vital for highly precise timing and navigation systems. These lasers operate by reflecting a beam between two mirrors within a cavity, maintaining a consistent beam speed. This precision is largely due to the chamber’s size stability, which neither expands nor contracts. To achieve this, mirrors are typically maintained in a cryogenic vacuum, insulated from external vibrations.

The moon hosts numerous craters at its poles, which lack direct sunlight due to minimal axial tilt. Consequently, these permanently shadowed areas are extremely cold, with some craters projected to reach temperatures around -253°C (20 Kelvin) during the lunar winter.

Junye from JILA, along with a research team in Boulder, Colorado, has proposed that these icy conditions, combined with the moon’s absence of natural vibrations and an almost non-existent atmosphere, make these craters ideal for ultra-stable lasers. The potential stability of these lunar lasers could surpass that of any terrestrial counterparts.

“The entire environment is incredibly stable,” Ye emphasizes. “Despite variations between summer and winter on the Moon, temperature fluctuations range only from 20 to 50 Kelvin, contributing to a remarkably consistent environment.”

Ye and his research team envision a lunar laser device akin to an optical cavity already developed in JILA’s lab, featuring a silicon chamber equipped with dual mirrors.

Current optical cavity lasers on Earth can maintain coherence for just a few seconds, meaning their light waves can synchronize briefly. However, the moon-based laser is projected to sustain coherence for at least a minute, which will facilitate its role as a reference laser for a variety of lunar missions. This includes maintaining the lunar time zone and coordinating satellite formations using lasers for distance measurement. Given that light from the moon takes just over a second to reach Earth, it could also serve as a reliable reference for Earth-based activities, as highlighted by Ye.

Although implementing this idea poses challenges, the rationale is sound and could greatly benefit future lunar missions. According to Simeon Barber from the Open University, UK, “Recent lunar landers have experienced suboptimal landings due to varying lighting conditions, complicating vision-based systems. Leveraging stable lasers for positioning, navigation, and timing could enhance the reliability of landings in high-latitude areas.”

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Source: www.newscientist.com

Ancient tattoo designs on mummies revealed by shining laser

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The tattooed hand of a 1200 year old mummy from Peru

Michael Pittman and Thomas G. Kaye

Laser scanning of a South American mummy reveals the intricate details of a tattoo dating back more than 1,200 years.

The mummy, belonging to a pre-Hispanic tribe known as the Chancays, was discovered in 1981 at the Cerro Colorado cemetery in Peru’s Huaura Valley.

It was obvious to the naked eye that many of the 100 mummies were tattooed, but the ink smeared beyond the boundaries of the original design and faded, making it impossible to see what the original markings looked like. It was impossible.

In a new study, michael pitman Researchers at the Chinese University of Hong Kong shined a laser on the specimens in a dark room and took long-exposure photographs. The laser brightened the skin and created a sharp contrast with the non-fluorescent tattoo ink.

This technique, which does not damage mummies, has never been used for tattoos before. Importantly, Pittman says, it shows not only where the ink is on the surface, but also where it is in the deeper layers of the skin.

“This allowed us to see the bleeding that had accumulated over the lifetime of the tattoo owner and reveal the original, finer design of the tattoo,” he says.

Researchers say the tattoo is so minute that it must have been created using a needle-and-ink technique using cactus needles or sharp animal bones, rather than a “cut-and-fill” method. That’s what I think.

Tattoos appear to have been important to the Chancay people, Pittman said, as they appear on the majority of known mummified human remains.

Forearm with Chancay mummy tattoo

Michael Pittman and Thomas G. Kaye

“Many of the designs, which are geometric patterns featuring triangles and diamonds, are also shared in other art mediums such as pottery and textiles, and some ceramic figures show geometric tattoo designs. Some are,” he says.

Some tattoos have intricate designs that seem to require special effort, while others are small and simple. “Thus, ancient Chancay tattoos show some similarities with the variations in design and significance that can be observed in tattoos today,” Pittman says.

Pittman says many traditional tattoos made by other ancient peoples can also be viewed in detail using laser-stimulated fluorescence technology. “We therefore plan to apply this method to other ancient tattoos from cultures around the world and try to make other interesting discoveries,” he says.

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Source: www.newscientist.com

Researchers use terahertz laser light to magnetize antiferromagnetic materials

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MIT physicists used a terahertz laser, a light source that oscillates more than 1 trillion times per second, to directly stimulate the atoms of an antiferromagnetic material. Their results are attracting attention because they provide new ways to control and switch antiferromagnetic materials and have the potential to advance information processing and memory chip technology.

Iliad others. demonstrated efficient manipulation of the magnetic ground state of layered magnets by a non-thermal route using terahertz light, and observed enhanced variations in order parameters as a promising area for exploring metastable hidden quantum states. The region near the critical point was established. Image credit: Adam Glanzman.

In a common magnet, known as a ferromagnetic material, the spins of the atoms point in the same direction, making the whole magnet susceptible to the influence of an external magnetic field and drawn in that direction.

In contrast, antiferromagnets are composed of atoms with alternating spins, with each atom pointing in the opposite direction from its neighbor.

This top, bottom, top, bottom order basically cancels out the spinout and gives the antiferromagnet a net zero magnetization that is unaffected by magnetic forces.

If memory chips could be made of antiferromagnetic materials, it would be possible to “write'' data into minute regions of the material called domains.

A certain configuration of spin orientation in a particular region (e.g., up-down) represents a classical bit ‘0’, and a different configuration (down-up) means ‘1’. Data written on such chips becomes robust against external magnetic influences.

For this reason, scientists believe that antiferromagnetic materials could provide a more robust alternative to existing magnetic-based storage technologies.

However, a major hurdle has been how to control antiferromagnets in a way that reliably switches the material from one magnetic state to another.

MIT professor Nuh Gedik and his colleagues were able to controllably switch antiferromagnets into new magnetic states using carefully tuned terahertz light.

“Antiferromagnetic materials are robust and unaffected by unwanted stray magnetic fields,” Professor Gedick said.

“But this robustness is also a double-edged sword: their insensitivity to weak magnetic fields makes these materials difficult to control.”

Researchers collaborated with FePS3a material that transitions to an antiferromagnetic phase at a critical temperature of about 118 K.

They thought that by tuning in to the vibrations of atoms, it might be possible to control the transitions of matter.

“You can imagine that any solid material has a periodic arrangement of different atoms, with little springs between them,'' said Dr. Alexander von Hogen of MIT.

“When you pull one atom, it vibrates at a unique frequency that typically occurs in the terahertz range.”

The way atoms vibrate is also related to how their spins interact.

Scientists believe that if they can stimulate atoms with a terahertz source called phonons, which vibrate at the same frequency as the atoms' collective vibrations, the effect will change the spins of the atoms from a perfectly balanced magnetically staggered state. It was inferred that there was a possibility of deviation.

When the balance is disrupted, the atoms have more spin in one direction than the other, creating a preferred orientation that moves the essentially unmagnetized material into a new magnetic state with finite magnetization.

“The idea is to kill two birds with one stone: we excite terahertz vibrations in atoms, which are also coupled to their spins,” Professor Gedick said.

To test this idea, they placed a sample of FePS.3 It was cooled to a temperature below 118K in a vacuum chamber.

They then generated terahertz pulses by directing a beam of near-infrared light at an organic crystal, converting the light to terahertz frequencies.

This terahertz light was then directed at the sample.

“This terahertz pulse is what is used to induce changes in the sample,” said Dr. Tianchuang Luo of MIT.

“It’s like ‘writing’ a new state to the sample.”

To confirm that the pulse caused a change in the material’s magnetism, the authors also aimed two near-infrared lasers, each with opposite circular polarization, at the sample.

Without the influence of the terahertz pulse, there should be no difference in the intensity of the transmitted infrared laser.

“Just seeing the differences tells us that the material is no longer the original antiferromagnetic material, but is essentially inducing a new magnetic state by shaking the atoms using terahertz light,” MIT said Dr. Bateer Ilyas.

Through repeated experiments, the researchers observed that the terahertz pulses were able to successfully switch previously antiferromagnetic materials into a new magnetic state. This transition persisted for a surprisingly long time, more than a few milliseconds, even after the laser was turned off.

“People have observed such light-induced phase transitions in other systems before, but typically their survival times are very short, on the order of picoseconds, or trillionths of a second. ,” Professor Gedick said.

of study Published in a magazine nature.

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B. Ilyas others. 2024. Near-critical terahertz field-induced metastable magnetization in FePS3. nature 636, 609-614; doi: 10.1038/s41586-024-08226-x

This article is a version of a press release provided by MIT.

Source: www.sci.news

Laser Beams Can Create Shadows with the Proper Conditions

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in new paper Published in today's magazine opticaphysicists explain how a laser beam casts a shadow that behaves like any other ordinary shadow.

Photographic image of the shadow of a laser beam. A high-powered green laser beam (object) passes through a ruby ​​cube and is illuminated from the side with blue light: (A) Photograph of the shadow cast by the object laser beam on a white piece of paper, imaged through a simple lens It will be magnified approximately 4 times using The length of the ruby ​​cube is approximately 1.2cm, and the enlarged image is approximately 4.8cm. Therefore, whether magnified or not, it depicts what can be seen directly. (B) Photographic image showing the surroundings for scale reference. Place a white plastic marker (i.e., a wide-tipped pen) in the path of the shadow between the object beam and the paper, and fix the camera focus on the (C) paper or (D) marker. The appearance of a shadow along the contours of the surface it falls on. All images were taken with a regular home digital camera in a dark room. Image credit: Abrahao others., doi: 10.1364/optica.534596.

“Laser light that casts shadows was previously thought to be impossible because light typically passes through other light without interacting,” said Dr. Rafael Abrahao, a researcher at Brookhaven National Laboratory. spoke.

“Demonstration of a highly counterintuitive optical effect prompts us to reconsider our concept of shadow.”

Dr. Abrahao and his colleagues used a ruby ​​crystal and a specific laser wavelength to show that laser beams can block light and create visible shadows through nonlinear optical processes.

This effect occurs when light interacts with a material in an intensity-dependent manner and can affect another light field.

“Our understanding of shadows has developed in close connection with our understanding of light and optics,” Dr. Abrahao said.

“This new discovery could prove useful in a variety of applications, including optical switching, devices in which one light controls the presence of another, or technologies that require precise control of light transmission, such as high-power lasers. There is a possibility that

In their experiment, the researchers shined a high-power green laser onto a cube made of a standard ruby ​​crystal, then shot a blue laser at it from the side.

When a green laser is incident on a ruby, it locally changes the material's response to blue wavelengths.

The green laser acts like a normal object, and the blue laser acts like a light.

The interaction between the two light sources creates a shadow on the screen, where the green laser appears as a dark area blocking the blue light.

It met all the criteria for a shadow, as it was visible to the naked eye, followed the contours of the surface it fell on, and followed the position and shape of the laser beam acting as the object.

The laser shadow effect is the result of ruby's optical nonlinear absorption.

This effect occurs because the green laser increases the light absorption of the blue illumination laser beam, creating a matching region within the illumination light with lower light intensity.

“This discovery expands our understanding of the interaction between light and matter and opens up new possibilities for harnessing light in previously unimagined ways,” Dr. Abrahao said.

The researchers experimentally measured that the shadow contrast depends on the power of the laser beam and found that the maximum contrast was about 22%, similar to the contrast of a tree's shadow on a sunny day.

They also developed a theoretical model and showed that it could accurately predict shadow contrast.

“From a technical point of view, the effect we demonstrated shows that the intensity of the transmitted laser beam can be controlled by firing another laser,” the scientists said.

“Next, we plan to investigate other materials and other laser wavelengths that can produce similar effects.”

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Raphael A. Abrahao others. 2024. Shadow of laser beam. optica 11 (11): 1549-1555;doi: 10.1364/optica.534596

Source: www.sci.news

Unearthed: Laser Technology Discovers Hidden Mayan City with Stone Pyramids in Mexico

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Archaeologists used a laser-based detection system to discover more than 6,500 Pre-Hispanic structures in Campeche, Mexico, including a previously unknown Mayan city named Valeriana.

Details of the main ruins of Valeriana in Campeche, Mexico. Image credit: Auld-Thomas others., doi: 10.15184/aqy.2024.148.

“Our analysis not only revealed a complete picture of densely populated areas, but also revealed a lot of variation,” said Tulane University doctoral student and Northern Arizona University professor. Lecturer Luke Old-Thomas said.

“What we found was not only rural areas and small settlements, but also a town where people had long been actively farming amidst the ruins, right next to the only main road in the area. We also found a large city with pyramids.”

“The government knew nothing about it. The scientific community knew nothing about it.”

“This is an exclamation point after the statement that, no, we haven't discovered everything. Yes, there's still a lot to discover.”

lidar technology It uses laser pulses to measure distance and create a 3D model of a specific area.

This allows scientists to scan vast tracts of land from the comfort of their computer labs, discovering anomalies in the landscape that turn out to be pyramids, family homes, and other examples of Mayan infrastructure. It's done.

“With LIDAR, we can map large areas very quickly and with very high accuracy and level of detail, so we can say, “Wow, there are so many buildings that we don't know about, and they must have a large population.'' ‘It's huge,’ said Old Thomas.

“The counterargument was that lidar surveys were still too constrained to known large sites like Tikal, thus creating a distorted picture of the Maya lowlands.”

“What if the rest of the Maya region is much more rural and what we've mapped so far is the exception rather than the rule?”

The team's results provide compelling evidence of a Maya landscape that was more complex and diverse than previously thought.

“Rider teaches us that, like many other ancient civilizations, the Lowland Maya built a diverse tapestry of towns and communities on a tropical landscape,” said Marcello Canuto, a professor at Tulane University. “I'm grateful for that,” he said.

“Some areas have vast expanses of farmland and are densely populated, while others have only small communities.”

“Nevertheless, we can now see how much the ancient Maya modified their environment to support a long-lasting and complex society.”

a paper The findings were published in the journal October 29, 2024. ancient.

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luke old-thomas others. 2024. Running out of space: Environmental riders and the crowded ancient landscape of Campeche, Mexico. ancient 98 (401): 1340-1358;doi: 10.15184/aqy.2024.148

Source: www.sci.news

The most powerful laser ever created is “Sound Laser”

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“Phonon laser” emits sound particles instead of light

Dmytro Radzinkov/Alamy

Tiny floating beads are the core of an unprecedentedly bright laser that fires particles of sound instead of light.

Just as light rays are made up of many particles called photons, sound is also made up of particle-like clumps called phonons. For decades, researchers have created “phonon lasers” that output these particles in narrow beams, similar to the way optical lasers emit photons.

Now, Hui Jin Researchers at Hunan Normal University in China have developed the brightest phonon laser ever.

The heart of their device was a silica bead about the size of a typical bacterium, roughly micrometers long. They used two beams of light to levitate a bead and surrounded it with a reflective cavity. The tiny vibrations of this bead generated phonons, which were captured and amplified within the cavity. This continued until there were enough phonons to form a laser-like beam.

Several research groups had previously tested similar designs. But Jin and his colleagues added electrodes directly beneath the beads to generate carefully selected electromagnetic signals. This modification increased the laser’s “brightness” (the amount of power delivered at each phonon frequency) by a factor of 10, making the beam tighter and longer lasting. Previous devices developed by Jin’s team and others could only operate for a few minutes, but the latest phonon lasers can operate for more than an hour.

Because phonons are less affected by traveling through liquids, they may be more effective than traditional lasers for imaging water tissue in biomedicine and some deep-sea monitoring devices, Jin said. To tell.

But Richard North Researchers from the Delft University of Technology in the Netherlands say the current experimental setup is too complex, requiring precise alignment of all components. Phonon lasers can require years of research and engineering before they can match the usefulness of comparable optical lasers.

“Given the impact optical lasers have had on modern life, there is excitement about phonon lasers, but only time will tell if they will have a comparable impact,” he says.

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Source: www.newscientist.com

Using laser light to simulate material production

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Researchers at Osaka University have simulated the collision of photons with lasers, potentially paving the way to creating matter from light in the laboratory. This advance in quantum physics has the potential to understand the composition of the universe and discover new physics. (Artist’s concept) Credit: SciTechDaily.com

A team led by researchers from Osaka University and the University of California, San Diego has demonstrated how to use simulations to experimentally create materials from light alone. This could one day help test long-standing theories about the composition of the universe.

One of the most shocking predictions of quantum physics is that matter can be created solely from light (or photons), and in fact, objects known as pulsars have accomplished this feat. Although producing matter directly in this way has not been achieved in the laboratory, it could allow further testing of fundamental quantum physics theories and the fundamental makeup of the universe.

In a recently published study, physical review letterA team led by researchers from Osaka University photon– Collision of photons using only lasers. The simplicity of the setup and ease of implementation at currently available laser intensities make it a promising candidate for experimental implementation in the near future.

Image of a self-organizing photon collider driven by intense laser pulses propagating through a plasma.Credit: Yasuhiko Sentoku

Photon-photon collisions are theorized to be the fundamental means by which matter is created in the universe, resulting from Einstein’s famous equation E=mc2. In fact, researchers have created materials indirectly from light by accelerating metal ions, such as gold, into each other at high speeds. At such high velocities, each ion is surrounded by photons, creating matter and antimatter as they pass each other.

However, it is difficult to generate materials experimentally using laser light alone in modern laboratories, as very high-power lasers are required. The researchers set out to simulate how this feat is accomplished in the lab because it could lead to experimental breakthroughs.

“Our simulations show that when interacting with the laser’s strong electromagnetic field, a dense plasma It can self-assemble to form a photon-photon collider,” explains Dr. Sugimoto, lead author of the study. “This collider contains a population of gamma rays that is 10 times denser than the electron density in the plasma, and whose energy is a million times greater than the energy of the photons in the laser.”

Self-organizing photon collider driven by intense laser pulses. (a) Plasma density, (b) magnetic channel, and (c) angular distribution of emitted photons. Credit: Physical Review Letters

Photon-photon collisions in a collider produce electron-positron pairs, which are accelerated by a plasma electric field generated by a laser. This produces a positron beam.

“This is the first simulation of an accelerated positron from a linear Breit-Wheeler process under relativistic conditions,” said co-author Professor Alefeyev from UCSD. “We feel that our proposal is experimentally feasible and we look forward to real-world implementation,” said Dr. Vyacheslav Lukin, program director at the National Science Foundation, which supported the research. It is stated as follows. “This research shows a potential way to explore the mysteries of the universe in a laboratory setting. The future possibilities for current and future high-power laser facilities have become even more interesting.”

Applying this research to Star Trek’s fictional matter and energy conversion technology remains mere fiction. Nevertheless, this research has the potential to help experimentally confirm theories of the composition of the universe, and may even help discover previously unknown physics.

Reference: “Positron generation and acceleration in a self-organizing photon collider enabled by ultra-intense laser pulses” K. Sugimoto, Y. He, N. Iwata, Illinois. Yeh, K. Tantartalakul, A. Alefyev, Y. Szenk, August 9, 2023. physical review letter.
DOI: 10.1103/PhysRevLett.131.065102

Source: scitechdaily.com

NASA’s Laser Technology Beams Ultra-HD Cat Video from 19 Million Miles Away

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NASA has made a significant advancement in deep space communications by successfully transmitting high-definition video from 19 million miles away. This breakthrough paves the way for advanced data transmission in space exploration. The video was transmitted from a cat named Taters and marked a historic milestone for NASA’s laser communications demonstration.

The Deep Space Optical Communications Experiment on December 11 transmitted ultra-high-resolution streaming video from a record-setting distance of 19 million miles. This milestone is part of a NASA technology demonstration aimed at streaming extremely high-bandwidth video and other data from deep space to enable future crewed missions beyond Earth orbit.

NASA Deputy Administrator Pam Melroy stated, “This achievement confirms our commitment to advancing optical communications as a key element in meeting future data transmission needs. Increasing bandwidth is essential to achieving future exploration and science goals, and we look forward to continued advances in this technology and the transformation of how we communicate during future interplanetary missions.”

The 15-second test video was transmitted using a Flight Laser Transceiver at a maximum bit rate of 267 Mbps and took 101 seconds to reach Earth. The instrument transmitted a coded near-infrared laser to the Hale Telescope at the Palomar Observatory, where it was downloaded. Each frame of the video was transmitted “live” to NASA’s Jet Propulsion Laboratory in real time.

The video was sent via a Deep Space Optical Communications (DSOC) technology demonstration flight laser transceiver that was installed at NASA’s Jet Propulsion Center in April 2021 and later integrated with NASA’s Psyche spacecraft. The technology aims to transmit data from deep space 10 to 100 times faster than the most advanced radio frequency systems used in today’s deep space missions.

The ultra-high-definition video features a cat named Taters and was transmitted from deep space on December 11, 2023. The video was part of a technology demonstration known as Deep Space Optical Communications (DSOC) as the Psyche spacecraft heads towards the asteroid belt between Mars and Jupiter.

The system has demonstrated faster data downlink speeds and increased pointing accuracy during weekly checkouts. The project demonstrated downlink bit rates of 62.5 Mbps, 100 Mbps, and 267 Mbps, comparable to broadband Internet download speeds. The team was able to download a total of 1.3 terabits of data during that time, marking a significant technological achievement.

Source: scitechdaily.com

Webb’s fresh perspective on supernovae, laser connections between space stations, and the Europa Clipper mission

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New high-definition images from NASA’s James Webb Space Telescope’s NIRCam (Near Infrared Camera) reveal intricate details of the supernova remnant Cassiopeia A (Cas A), which is struck by a gas outlet by a star before exploding. It shows an expanding shell of matter. Credits: NASA, ESA, CSA, STScI, Danny Milisavljevic (Purdue University), Ilse De Looze (UGent), Tea Temim (Princeton University)

NASAWebb Space Telescope observes newly exploded star…

The team prepares to install the moon rocket hardware…

And we completed NASA’s first bidirectional end-to-end laser relay system…

Some of the stories we want to share with you – this week at NASA!

Watch the web’s new high-definition exploded stars

NASA’s James Webb Space Telescope recently captured this new image of supernova remnant Cassiopeia A. This image, taken with Webb’s near-infrared camera, shows the star’s explosion at a resolution previously unattainable at these wavelengths, giving astronomers a hint at the dynamic processes occurring. . It’s inside a supernova remnant.

NASA’s Artemis II mission is making final preparations for its SLS rocket at Kennedy Space Center. The Orion stage adapter, a critical component that connects Orion to his SLS, recently underwent critical installation work on its diaphragm at Marshall Space Flight Center. This adapter plays an important role in preventing hydrogen gas buildup and ensuring safety during launch.Credit: NASA/Sam Lott

Team prepares to assemble moon rocket and spacecraft connectors

A team at NASA’s Marshall Space Flight Center recently flipped the Orion stage adapter over and prepared the adapter for diaphragm installation.

The stage adapter connects the Orion spacecraft to the Space Launch System rocket’s intermediate cryogenic propulsion stage (ICPS). The diaphragm helps prevent highly flammable hydrogen gas, which could leak from the rocket’s propellant tanks, from accumulating beneath Orion and its crew before and during launch.

NASA’s ILLUMA-T payload communicates with the LCRD via laser signals.Credit: NASA/Dave Ryan

Space station laser communication terminal achieves first link

NASA’s LCRD and the new space station technology experiment ILLUMA-T successfully exchanged data for the first time, establishing the first laser link between ILLUMA-T and an on-orbit laser relay system. LCRD and his ILLUMA-T teamed up to complete NASA’s first bidirectional end-to-end laser relay system.

Laser communications uses infrared light rather than traditional radio waves to send and receive signals, allowing spacecraft to pack more data into each transmission.

The “Message in a Bottle” campaign offers anyone the opportunity to stencil their name onto a microchip inscribed with U.S. Poet Laureate Ada Limón’s “Mystery Praise: A Poem to Europe.” The chip will be mounted on NASA’s Europa Clipper spacecraft, bound for Jupiter and its moon Europa. Credit: NASA

Add your name to join the European Clipper Mission

The deadline to participate in NASA’s European Clipper mission’s Message in a Bottle campaign is 11:59 p.m. EST, December 31, 2023. You can join the mission and carve your name on his Clipper spacecraft as it travels and explores 1.8 billion miles of Europe. Jupitericy moon, Europa.

For more information, visit go.nasa.gov/MessageInABottle.

What’s happening this week at @NASA!

Source: scitechdaily.com

Shrinking Ultra-High-Speed Laser to Fit on a Fingertip

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A breakthrough in laser technology has been achieved by miniaturizing an ultrafast mode-locked laser onto a nanophotonic chip using thin-film lithium niobate. This advancement paves the way for compact and efficient lasers with wide applications in imaging, sensing, and portable technologies.


New advances enable detailed execution in pocket-sized devices.

GPS – Free high-precision navigation, medical image processing, food safety inspection, etc.



Lasers are essential tools for observing, detecting, and measuring things in nature that cannot be seen with the naked eye. However, the ability to perform these tasks is often limited by the need to use expensive and bulky equipment.


Innovation in ultrafast laser technology

In a new cover story paper published in a magazine scienceIn , researcher Qiushi Guo demonstrates a new approach to creating high-performance, ultrafast lasers on nanophotonics chips. His research focuses on the miniaturization of mode-locked lasers. A mode-locked laser is a unique laser that emits a series of ultrashort coherent light pulses at femtosecond intervals, which is an astonishing one quadrillionth of a second.

Chip-scale ultrafast mode-locked laser based on nanophotonic lithium niobate.Credit: Alireza Marandi


Unraveling nature’s fastest timescales



Ultrafast mode-locked lasers are essential for unlocking the secrets of nature’s fastest timescales, such as the formation and breaking of molecular bonds during chemical reactions and the propagation of light through turbulent media. The high speed, pulse peak intensity, and wide spectral coverage of mode-locked lasers also enable numerous photonics technologies, such as optical atomic clocks, biological imaging, and computers that use light to calculate and process data. Ta.


Unfortunately, state-of-the-art mode-locked lasers are currently expensive, power-hungry benchtop systems that are limited to laboratory use.

Aiming for smaller and more efficient photonics

“Our goal is to revolutionize the field of ultrafast photonics by converting large lab-based systems into chip-sized systems that can be mass-produced and deployed in the field.” said Guo, a faculty member in the Photonics Initiative at the University’s Center for Advanced Science Research. Professor of Physics at New York University Graduate Center.

“In addition to miniaturization, we want to ensure that these ultrafast chip-sized lasers can provide satisfactory performance. requires sufficient pulse peak strength, preferably 1 watt or more.”

Challenge to miniaturization

However, achieving an effective mode-locked laser on a chip is not a simple process. Guo’s research leverages an emerging materials platform known as thin-film lithium niobate (TFLN). This material allows highly efficient shaping and precise control of laser pulses by applying external radio frequency electrical signals.

In their experiments, Guo’s team created a unique combination of III-V high laser gain. semiconductor TFLN’s efficient pulse shaping function nanoscale Using photonic waveguides, we demonstrate a laser capable of emitting high output peak power of 0.5 watts.

Future impacts and challenges

Beyond its compact size, the demonstrated mode-locked laser also exhibits many interesting properties that are unattainable with conventional lasers, leading to deep implications for future applications. For example, by adjusting the laser’s pump current, Guo was able to precisely tune the output pulse repetition frequency over a very wide range of 200 MHz. By leveraging the demonstrated strong reconfigurability of lasers, the research team hopes to realize chip-scale, frequency-stabilized comb light sources, which are essential for high-precision sensing.

Guo’s team still needs to take on additional challenges to achieve scalable, integrated, ultrafast photonic systems that can be translated for use in portable and handheld devices, but his lab has demonstrated ​​Overcame a major obstacle in the construction.

Potential real-world applications

“This achievement paves the way to eventually use mobile phones to diagnose eye diseases and analyze food and the environment for E. coli and dangerous viruses,” Guo said. “This could also enable futuristic chip-scale atomic clocks that enable navigation even when GPS is compromised or unavailable.”

Learn more about this breakthrough advancement below.

Reference: “Ultrafast mode-locked lasers in nanophotonic lithium niobate” Qiushi Guo, Benjamin K. Gutierrez, Ryotosekine, Robert M. Gray, James A. Williams, Luis Ledezma, Luis Costa, Arkadev Roy, Selina Zhou, Mingchen Liu, and Alireza Marandi, November 9, 2023; science.
DOI: 10.1126/science.adj5438

Source: scitechdaily.com