Increasing future gravitational-wave detectors’ sensitivity by means of amplitude filter cavities and quantum entanglement

Abstract

The future laser interferometric gravitational-wave detectors' sensitivity can be improved using squeezed light. In particular, recently a scheme which uses the optical field with frequency-dependent squeeze factor, prepared by means of a relatively short ({approx}30 m) amplitude filter cavity, was proposed [Thomas Corbitt, Nergis Mavalvala, and Stan Whitcomb, Phys. Rev. D 70, 022002 (2004).]. Here we consider an improved version of this scheme, which allows one to further reduce the quantum noise by exploiting the quantum entanglement between the optical fields at the filter cavity two ports.