Lecturer: Mr. Lior Cohen, Racah Institute of Physics, The Hebrew University of Jerusalem
Abstract:
One of the most common ways to sense and measure the physical world is by using light, and in particular by interferometric measurements. The Laser Interferometer Gravitational-Wave Observatory is an extreme example for that. Classically, these measurements are limited to Rayleigh-diffraction-limit resolution and shot-noise-limit (SNL) sensitivity. Using quantum mechanics, one can surpass these limits.
In the main part of the talk, I will show a few interferometric experiments. The first experiment presents interferometric measurements showing sub-wavelength super-resolved features at the SNL. This is a result of measuring the parity of a weak coherent state, a measurement without a classical analog. The second experiment shows how SNL can be preserved in a noisy environment, using quantum error correction. The same scheme can preserve also the Heisenberg limit (i.e. sub-SNL). The last presented experiment constructs entangled coherent states which exhibit deterministically both super-resolution and Heisenberg limited sensitivity.
Also, one main tool of those works, a photon number resolving detector, and its calibration, will be presented.