Four-wave mixing with a new phase-matching geometry

Xuan-Jian He, Gao-Feng Jiao, Jun Jia, L. Q. Chen, Weiping Zhang, Chun-Hua Yuan

Published 2019-02-27Version 1

A nondegenerate intensity-squeezed twin beams has been produced with a four-wave mixing (4WM) process driven by two pump fields cross a small angle [Jia \emph{et al.}, Opt. Lett. 42, 4024 (2017)]. We theoretically study this 4WM process and find that this process is implemented under a new 4WM phase matching condition, and the refractive index of the corresponding probe light $n_{p}$ can be converted between greater than $1$ and less than $1$ by angle adjustment, which can be used to obtain $2$ different time order output pulses. With exchange of the roles of the pump beams and the probe and conjugate beams, the twin beams with frequency degenerate but separated spatial patterns can be realized. In the region with $n_{p}<1$, the bandwidth of the gain is relatively large, which is advantageous for realizing a wide bandwidth intensity-squeezed light. Due to the bandwidth is important for the practical application of quantum memory, the wide bandwidth intensity-squeezed light fields provides new prospects for quantum memory.