Detuned Twin-Signal-Recycling for ultrahigh-precision interferometers

Opt Lett. 2007 Apr 15;32(8):985-7. doi: 10.1364/ol.32.000985.

Abstract

We propose a new interferometer technique for high-precision phase measurements such as those in gravitational wave detection. The technique utilizes a pair of optically coupled resonators that provide identical resonance conditions for the upper as well the lower phase modulation signal sidebands. This symmetry significantly reduces the noise spectral density in a wide frequency band compared with single-sideband recycling topologies of current and planned gravitational wave detectors. Furthermore, the application of squeezed states of light becomes less demanding.