Back-action cancellation in interferometers by quantum locking
Laboratoire Kastler Brossel, Case 74 - 4 place Jussieu
F-75252 Paris Cedex 05, France
Accepted: 22 May 2003
We show that back-action noise in interferometric measurements such as gravitational-waves detectors can be completely suppressed by a local control of mirrors motion. An optomechanical sensor with an optimized measurement strategy is used to monitor mirror displacements. A feedback loop then eliminates radiation-pressure effects without adding noise. This very efficient technique leads to an increased sensitivity for the interferometric measurement, which becomes only limited by phase noise. Back-action cancellation is furthermore insensitive to losses in the interferometer.
PACS: 42.50.Lc – Quantum fluctuations, quantum noise, and quantum jumps / 04.80.Nn – Gravitational wave detectors and experiments / 03.65.Ta – Foundations of quantum mechanics; measurement theory
© EDP Sciences, 2003