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arXiv · 1312.7612

Photon emission via vacuum-dressed intermediate states under ultrastrong coupling

Jin-Feng Huang·C. K. Law
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Abstract

We investigate theoretically quantum effects of a cavity-atom system in which the upper two levels of a cascade-type three-level atom interact with a cavity field mode in the ultrastrong coupling regime. By exploiting the virtual photons carried by atom-cavity dressed states, we indicate how two external driving fields induce Raman transitions such that a continuous conversion of virtual photons into real photons can be achieved with a high probability. We present analytical and numerical solutions of the system. In addition, we show that the converted photons exhibit a bunching behavior in the steady state. Our scheme demonstrates that atom-cavity dressed states in the ultrastrong coupling regime can serve as intermediate states to invoke nonlinear optical processes.

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Jin-Feng Huang, C. K. Law. 2013-12-30. Photon emission via vacuum-dressed intermediate states under ultrastrong coupling. https://doi.org/10.1103/physreva.89.033827

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