Path length modulation technique for scatter noise immunity in squeezing measurements.

We present a technique for frequency shifting scattering induced noise on squeezed light beams, providing immunity from scattered light while preserving the squeezed states. Using a 500 Hz pre and postsqueezing apparatus path length modulation, we show up to a 20 dB reduction in scattering induced noise while recovering squeezing measurement below the shot noise level. Such a technique offers immunity to spurious scattering sources without the need for optically lossy isolation optics.

Backscatter tolerant squeezed light source for advanced gravitational-wave detectors.

We report on the performance of a dual-wavelength resonant, traveling-wave optical parametric oscillator to generate squeezed light for application in advanced gravitational-wave interferometers. Shot noise suppression of 8.6±0.