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arXiv · 1603.00728

Superradiant Emission of Ultra-Bright Photon Pairs in Doppler-Broadened Atomic Ensemble

Yoon-Seok Lee·Sang Min Lee·Heonoh Kim·Han Seb Moon
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Abstract

With a recent rising interest of single photon superradiance due to its potential usefulness for efficient collection of single photon from an atomic ensemble, bright and narrow photon pair source is a key component in realization of quantum communication and quantum computer based on coherent interaction between light and atomic ensemble. We report the superradiant emission of ultra-bright photon pairs with a coincidence counting rate per input power of 64,600 cps/mW via spontaneous four-wave mixing in a thermal vapour cell. The photon-pair generation rate is enhanced by the contribution of two-photon coherence of almost atomic velocity groups in the Doppler-broadened ladder-type atomic system. The quadratic proportionality of the probability of detecting a heralded single photon as a function of the optical depth clarifies that the ultra-brightness results from the superradiance. In addition, a single photon superradiant beating at a high optical depth of the atomic ensemble is observed for the first time.

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Yoon-Seok Lee, Sang Min Lee, Heonoh Kim, Han Seb Moon. 2016-03-02. Superradiant Emission of Ultra-Bright Photon Pairs in Doppler-Broadened Atomic Ensemble. https://arxiv.org/abs/1603.00728

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