Aashish Clerk: Non-classical noise in quantum optomechanical systems

Monday, June 25, 2012 12:30 pm - 1:30 pm EDT (GMT -04:00)

Aashish Clerk, McGill University

Abstract

A key goal in the fields of quantum optomechanics and electromechanics is to measure and hopefully control truly quantum behaviour in a "large" mechanical resonator. In this talk, I will start by giving a quick introduction to these two rapidly growing fields. I will then discuss recent experimentally-motivated theoretical work which calculates the full statistics of low-frequency energy fluctuations of a driven, quantum resonator. Surprisingly, these fluctuations are highly non-classical: they are most naturally described by a quasi-probability distribution which can be negative. Somewhat surprisingly, this effect has a close relationship to the statistics of electronic charge transfer (so-called "full counting statistics") in mesoscopic superconducting conductors. I will discuss how these effects might be measured, and how they represent a kind of non-classical behaviour similar to the violation of a Leggett-Garg inequality. They also suggest a general method for characterizing non-classical temporal correlations. While the emphasis is on phonons, our results apply equally as well to the photon fluctuations of a driven cavity.