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Torque is a torsional force that often causes rotation and is a device for measuring system torque and comes in many forms and sizes. In recent years, scientists have been studying ways to reduce the size of torque sensors in order to facilitate the measurement of very small torques. Currently, researchers have developed microdevices that use nanofabrication and cryogenic cooling to study studies such as the Casimir effect and small-scale magnetism. Prior to this new work, the sensitivity of the most sensitive torque sensor at milli-Kelvin temperature was 2.9 × 10−24 N m Hz−1 / 2, and Purdue ’s team set a goal for itself to break this record.
The new torque measurement device consists of a silica nanoparticle suspended in a vacuum chamber by a 500 mW, 1550 nm laser beam. The research team applied a torque to the nanoparticles by emitting a pulsating circularly polarized 1020nm laser beam to the nanoparticles for 100 seconds at a time. Researchers use a quarter-wave plate to control polarization, and the rotating waves in the electromagnetic beam exert a twist on the nanoparticles, causing them to rotate at 300 billion rpm, the fastest man-made ever made. Rotor. The research team was able to measure the amount of torque in the device by using optical sensors to measure changes in the spin speed of particles during the switching cycle. The researchers point out that, unlike other systems under development, their systems do not require complex nanofabrication.
Using this torque measuring device, researchers were able to measure three-quarters of the torque of a torque Newton meter, making it 700 times more sensitive than previous torque sensors. They claim that their device will be the first to measure vacuum friction, in which quantum mechanics shows that objects rotating in a vacuum will be dragged by the constantly appearing and disappearing electromagnetic fields. The team also claims that the torque measuring device can be used for nanomagnetic research and quantum geometric phase research.