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Can optical squeezing be generated via polarization self-rotation in a thermal vapour cell?

M. T. L. Hsu·A. Dantan·J. Cviklinski·A. Bramati·G. Hetet·A. Peng·C. C. Harb·H. -A. Bachor·M. T. Johnsson·J. J. Hope·M. Pinard·P. K. Lam
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Abstract

The traversal of an elliptically polarized optical field through a thermal vapour cell can give rise to a rotation of its polarization axis. This process, known as polarization self-rotation (PSR), has been suggested as a mechanism for producing squeezed light at atomic transition wavelengths. In this paper, we show results of the characterization of PSR in isotopically enhanced Rubidium-87 cells, performed in two independent laboratories. We observed that, contrary to earlier work, the presence of atomic noise in the thermal vapour overwhelms the observation of squeezing. We present a theory that contains atomic noise terms and show that a null result in squeezing is consistent with this theory.

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M. T. L. Hsu, A. Dantan, J. Cviklinski, A. Bramati, G. Hetet, A. Peng, C. C. Harb, H. -A. Bachor, M. T. Johnsson, J. J. Hope, M. Pinard, P. K. Lam. 2005-10-24. Can optical squeezing be generated via polarization self-rotation in a thermal vapour cell?. https://doi.org/10.1103/physreva.73.023806

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