Lecturer: Dr. Itay Shomroni, Postdoctoral Fellow, Laboratoire de Photonique et de Mesure Quantique, EPFL Station 3, CH-1015 Lausanne, Switzerland
Abstract:
Quantum optomechanics, the study of mechanical motion in the quantum regime
using light, is an emerging field with applications ranging from sensing to
quantum information to exploring the classical-to-quantum transition. Although
its foundations had been laid in the 60s and 70s, quantum effects in macroscopic
mechanical motion, such as motional sideband asymmetry, radiation pressure shot
noise, and ponderomotive squeezing, have been observed only in the recent decade,
with advances in high-finesse microcavities. Mechanical oscillators based on
photonic crystals are one of the most promising systems for probing and
manipulating quantum motion, allowing efficient cooling to the motional ground
state using light as well as quantum-coherent operations. I will describe my
recent research with these systems, which includes the first demonstration of
backaction-evading measurement of mechanical motion in the optical domain. Such
measurement, originally proposed in the context of gravitational wave detection,
allows in principle arbitrary sensitivity by measuring only a single quadrature
of the motion, beating the quantum limit imposed by Heisenberg's uncertainty
relation. In addition, entering the regime of strongly-probed mechanical systems
close to their ground state has revealed novel phenomena such as interplay of
optomechanics and other Kerr-type effects, and new dynamics that may lead to
extraordinary instabilities. Quantum optomechanics is now entering a new era where
full quantum control is feasible, and I will give my outlook and possible future
directions.