Researchers of the Schliesser Lab at the Niels Bohr Institute, University of Copenhagen, have pushed the precision of force and position measurements into a new regime. Their experiment is the first to surpass the so-called “Standard Quantum Limit,” or SQL, which arises in the most common (and successful) optical techniques for ultra-precise position measurements. For more than 50 years, experimentalists have raced to beat the SQL using a variety of techniques, but to no avail. In their recent work, the researchers at the Niels Bohr Institute have done the trick with a simple modification of the standard approach, which enables the necessary cancellation of quantum noise in the measurement. The result and underlying experiment have potential implications for gravitational wave astronomy techniques, as well as force microscopy with biological applications. The work is now published in the prestigious scientific magazine, Nature Physics.
Source:
https://phys.org/news/2019-05-quantum-limit-precision-position.html