Frequency-noise cancellation in optomechanical systems for ponderomotive squeezing

Ponderomotive squeezing of the output light of an optical cavity has been recently observed in the megahertz range in two different cavity optomechanical devices. Quadrature squeezing becomes particularly useful at lower spectral frequencies, for example, in gravitational wave interferometers, despite being more sensitive to excess phase and frequency noise. Here we show a phase and frequency-noise cancellation mechanism due to destructive interference which can facilitate the production of ponderomotive squeezing in the kilohertz range and we demonstrate it experimentally in an optomechanical system formed by a Fabry-Perot cavity with a micromechanical mirror.