Gravitational wave memory and quantum Michelson interferometer
We examined the output of a quantum Michelson interferometer incorporating the combined effects of nonlinear optomechanical interaction and time-varying gravitational fields. Our findings indicate a deviation from the standard relationship between the phase shift of the interferometer's output and the amplitude of gravitational waves. This deviation, a slight offset in direct proportionality, is associated with the gravitational wave memory effect under the conventional settings of interferometer parameters. Furthermore, the results suggest that consecutive gravitational wave memory, or the stochastic gravitational wave memory background (SGWMB), contributes not only to the classical red noise spectrum but also to a quantum red noise spectrum through this new mechanism. This leads to a novel quantum noise limit for interferometers, which may be crucial for higher precision detection system. Our analysis potentially offers a more accurate description of quantum interferometers responding to gravitational waves and applies to other scenarios involving time-varying gravitational fields. It also provides insights and experimental approaches for exploring how to unify the quantum effects of macroscopic objects and gravitation.