Breakthrough: First-Ever Measurement of Pressure from Individual Particles

A groundbreaking device utilizing tiny beads stabilized by laser technology has made it possible to measure the pressure created by individual particles for the first time. This remarkable innovation holds potential for uncovering elusive particles that may constitute dark matter.

Pressure arises when particles collide with an object, applying force across its surface area. Traditionally, this phenomenon is viewed in averages, but during low-pressure environments, such as near-perfect vacuums, it becomes essential to monitor each particle’s contribution to accurately measure pressure.

Tseng Yuhan from Yale University and colleagues have engineered the first device capable of performing these precise measurements. At its core is a small silica sphere, measuring half the size of certain viruses, suspended in place by a laser beam through electromagnetic interactions. Each time a particle impacts the sphere, the reflected light can be captured and analyzed by researchers.

To evaluate this innovative system, the team placed the device in an ultra-high vacuum and gradually introduced three different gaseous particles. They meticulously measured the device’s movement upon particle collision, calculating pressure from these data points and comparing results to theoretical predictions, achieving impressive consistency. This indicates that the device is functioning as intended.

“Every detail is crucial for accurate measurements,” Tseng states. “We executed each step with precision, leading to beautiful results.”

Research conducted by Clark Hardy, and his team at Yale University, suggests this innovative device could redefine ultra-high vacuum standards, a realm where traditional pressure sensors often fail. “Counting individual particle collisions is sufficient to estimate pressure in these extremely high vacuum environments,” he explains.

“Observing individual molecular collisions in real-time is a rarity,” comments Joseph Kelly from King’s College London. “Typically, their effects are only perceived in averages, similar to how fast-moving objects appear blurred in long-exposure photography.”

Animesh Dutta, a researcher at the University of Warwick, indicates that similar instrument designs could significantly advance astronomical studies, particularly in understanding the dynamics of low-pressure interstellar spaces by detecting gaseous particles that other sensors might overlook.

The research team is also focused on using this device to detect hypothetical sterile neutrinos, a potential key to resolving a longstanding anomaly in particle physics experiments, elucidating the existence of incredibly small mass particles, and possibly identifying the fundamental composition of dark matter.