Radiation-pressure effects upon a micromirror in a high-finesse optical cavity

Recent progress in high-finesse optical cavities and micro-mechanical resonators allows one to reach a new regime in which both mechanical and optical dynamics are governed by the radiation pressure exerted by light on mirrors. This optomechanical coupling leads to the existence of fundamental quantum limits in ultrasensitive interferometric measurements, and also to very efficient cooling mechanisms of micromirrors. We experimentally study these effects by monitoring in a very high-finesse cavity the displacements of a mirror coated on a microresonator. Directs effects of intracavity radiation pressure are experimentally demonstrated: we have observed a self-cooling of the resonator induced by the intracavity radiation pressure, to effective temperature in the 10 K range. Further experimental progress and cryogenic operation may allow for quantum optics experiments and lead to the experimental observation of the quantum ground state of a mechanical resonator.