Optical Engineering

Effects of cavity detuning on squeezing in the generation of squeezed light at 1064 nm

Fei Feng, Jiazheng Song, Wenyan Qu, Tongyi Zhang

Published Aug 15, 2014• 0 citations

Abstract

We investigate the effects of cavity detuning on squeezing in the generation of the squeezed light at 1064 nm with a degenerate optical parametric amplifier (OPA) based on a periodically poled KTiOPO4 crystal. We theoretically analyze several effects that lead to cavity detuning, including the displacement and tilt of the incident laser light and the cavity length fluctuations of the OPA. To reduce the influence of the cavity detuning and increase the degree of generated quantum noise reduction, a side-of-fringe locking technique is applied to achieve the resonance between the OPA cavity and the injected laser beam. The experimental results show that the transmitted power through the locked cavity is increased and the cavity detuning is greatly suppressed. After locking of the cavity, we could expect to get a value for the control loop with an accuracy of 10−9 and the locking time is not less than 2 h, which paves the way for the preparation of the squeezed light.

DOI: 10.1117/1.oe.53.8.086106

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