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arXiv · 1803.02882

Compact sub-kilohertz low-frequency quantum light source based on four-wave mixing in cesium vapor

Rong Ma·Wei Liu·Zhongzhong Qin·Xiaolong Su·Xiaojun Jia·Junxiang Zhang·Jiangrui Gao
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Abstract

Using a nondegenerate four-wave mixing (FWM) process based on a double-Λ scheme in hot cesium vapor, we demonstrate a compact diode-laser-pumped quantum light source for the generation of quantum correlated twin beams with a maximum squeezing of 6.5 dB. The squeezing is observed at a Fourier frequency in the audio band down to 0.7 kHz which, to the best of our knowledge, is the first observation of sub-kilohertz intensity-difference squeezing in an atomic system so far. A phase-matching condition is also investigated in our system, which confirms the spatial-multi-mode characteristics of the FWM process. Our compact low-frequency squeezed light source may find applications in quantum imaging, quantum metrology, and the transfer of optical squeezing onto a matter wave.

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Rong Ma, Wei Liu, Zhongzhong Qin, Xiaolong Su, Xiaojun Jia, Junxiang Zhang, Jiangrui Gao. 2018-03-07. Compact sub-kilohertz low-frequency quantum light source based on four-wave mixing in cesium vapor. https://doi.org/10.1364/ol.43.001243

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