Phase-sensitive manipulation of squeezed vacuum via a dual-recycled Michelson interferometer.

The injection of squeezed vacuum state is an indispensable technology for the next generation gravitational wave observatory, which will open up a much larger window to the universe. After analyzing the absorption and dispersion properties of the reflected field of the dual-recycled Michelson interferometer (DRMI), we propose the phase-sensitive manipulation scheme of squeezed vacuum by utilizing the coupled-resonator-induced transparency in a dual-recycled Michelson interferometer (DRMI). In this way, the rotation frequency of squeezing ellipse can be finely tuned by the coupling strength, which overcome the limitation of the current solution (with a fixed rotation frequency) that employs a Fabry-Perot optical cavity as phase-sensitive manipulation element. This work will unleash the potential applications for quantum metrology beyond the shot noise limit.