Generation of amplitude-squeezed states by nondegenerate four-wave mixing with idler measurement feedback
Xi-Zeng Li, Zhenfeng Hu, Lixin Li · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1992
If the idler photon flux is continuously measured in a photon-counting detector and the photocurrent fluctuations are fed back to control the pump intensity, the output signal state will be an amplitude-squeezed state (near-number state) at low frequencies and high feedback loop gain. Electromagnetic field in number-phase minimum-uncertainty states (amplitude- squeezed states), and its limit (photon-number states) have potential applications in optical communication, precision measurement, and atomic spectroscopy, and gravitational wave detection. These states have been the focus of considerable attention.