Talk on "Quantum nondemolition measurement of optical field fluctuations by optomechanical interaction"

08.11.2018 15:30 - 16:45

by Francesco Marin; Physics Department, University of Florence, I

According to quantum mechanics, if we keep observing a continuous variable we generally disturb its evolution. For a class of observables, however, it is possible to implement a so-called quantum nondemolition measurement: by confining the perturbation to the conjugate variable, the observable is estimated with arbitrary accuracy, or prepared in a known state. For instance, when the light bounces on a movable mirror, its intensity is not perturbed (the effect is just seen on the phase of the radiation), but the radiation pressure allows one to trace back its fluctuations by observing the mirror motion. This idea is implemented a cavity optomechanical experiment based on an oscillating micromirror. We measure the correlation between the output light intensity fluctuations and the mirror motion and we demonstrate that the uncertainty of the former is reduced below the shot-noise level.  


Host: M. Aspelmeyer

Seminarroom 3, Boltzmanngasse 5, 5. Stk., 1090 Wien