In quantum optomechanics, radiation pressure from light or microwave fields couples mechanical and optical degrees of freedom at the quantum level.
There is currently a big international push to utilise this coupling to achieve truly non-classical behaviour in macroscopic mechanical oscillators. This could not only further our understanding of the physical world, but also allow new technologies such as ultra-sensitive mass or spin sensors capable of detecting single atoms, or memories and state transfer for quantum computers.
Key capabilities for achieving quantum optomechanics include the ability to measure the mechanical oscillator with resolution close to or surpassing its zero-point motion; the possibility to feedback control the mechanical state based on measurement results; and access to mechanical nonlinearities to generate non-classical states. Our group is pursuing each of these capabilities. Recent results include:
-  Discovery of new quantum thermodynamic effects that occur in mechanical systems operating beyond the regime of validity of the rotating wave approximation arXiv:1705.09174 [quant-ph](2017)
-  Proposal of an interface that allows quantum state transfer between light/microwaves and mechanical oscillators and functions outside of the usual good cavity limit arXiv:1704.07032 [quant-ph] (2017)
-  Demonstration of a new approach to generate nonclassical macroscopic states of mechanical motion Nature Communications 7, Article number: 10988 (2016)
-  Demonstration of strong classical mechanical squeezing using electrically induced parametric nonlinearity and weak measurement Physical Review Letters 110, 184301 (2013)
-  Proposal of a method to generate strong mechanical squeezing using parametric nonlinearities and weak measurement Physical Review Letters 107, 213603 (2011)
See also the book Quantum optomechanics, CRC press, 2015:
Written by Warwick P. Bowen and Gerard J. Milburn, Quantum Optomechanics discusses modern developments in this field from experimental and theoretical standpoints. The authors share their insight on a range of important topics, including optomechanical cooling and entanglement; quantum limits on measurement precision and how to overcome them via back-action evading measurements; feedback control; single photon and nonlinear optomechanics; optomechanical synchronization; coupling of optomechanical systems to microwave circuits and two-level systems, such as atoms and superconducting qubits; and optomechanical tests of gravitational decoherence.