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arXiv · 1705.02914

Multi-pass configuration for Improved Squeezed Vacuum Generation in Hot Rb Vapor

Mi Zhang·Melissa A. Guidry·R. Nicholas Lanning·Zhihao Xiao·Jonathan P. Dowling·Irina Novikova·Eugeniy E. Mikhailov
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Abstract

We study a squeezed vacuum field generated in hot Rb vapor via the polarization self-rotation effect. Our previous experiments showed that the amount of observed squeezing may be limited by the contamination of the squeezed vacuum output with higher-order spatial modes, also generated inside the cell. Here, we demonstrate that the squeezing can be improved by making the light interact several times with a less dense atomic ensemble. With optimization of some parameters we can achieve up to -2.6 dB of squeezing in the multi-pass case, which is 0.6 dB improvement compared to the single-pass experimental configuration. Our results show that other than the optical depth of the medium, the spatial mode structure and cell configuration also affect the squeezing level.

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Mi Zhang, Melissa A. Guidry, R. Nicholas Lanning, Zhihao Xiao, Jonathan P. Dowling, Irina Novikova, Eugeniy E. Mikhailov. 2017-05-10. Multi-pass configuration for Improved Squeezed Vacuum Generation in Hot Rb Vapor. https://doi.org/10.1103/physreva.96.013835

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