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arXiv · 1803.08911

Darkness of two-mode squeezed light in {\Lambda}-type atomic system

E. S. Moiseev·Arina Tashchilina·S. A. Moiseev·A. I. Lvovsky
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Abstract

We show that, under certain circumstances, an optical field in a two-mode squeezed vacuum (TMSV) state can propagate through a lossy atomic medium without degradation or evolution. Moreover, the losses give rise to that state when a different state is initially injected into the medium. Such a situation emerges in a {\Lambda}-type atomic system, in which both optical transitions are driven by strong laser fields that are two-photon resonant with the respective signal modes. Then the interactions of the two signal modes with the ground-state atomic coherence interfere destructively, thereby ensuring the preservation of the TMSV with a particular squeezing parameter. This mechanism permits unified interpretation of recent experimental results and predicts new phenomena.

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E. S. Moiseev, Arina Tashchilina, S. A. Moiseev, A. I. Lvovsky. 2018-03-23. Darkness of two-mode squeezed light in {\Lambda}-type atomic system. https://doi.org/10.1088/1367-2630%2Fab5fac

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