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arXiv · 2112.07580

Spatial Coherence of Light in Collective Spontaneous Emission

D. C. Gold·P. Huft·C. Young·A. Safari·T. G. Walker·M. Saffman·D. D. Yavuz
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Abstract

When a quantum system is put into an excited state, it will decay back to the ground state through a process termed spontaneous emission. It is generally assumed that spontaneous emission between different individual emitters would not be coherent with each other; to produce coherent light one would need population inversion and stimulated emission. In this work, we show that an optically-thin ensemble of 11,000 radiating atoms spontaneously organize to produce spatially coherent light. The reason for this coherence is collective-coupling of the individual emitters via Dicke superradiance and subradiance (as opposed to amplification through stimulated emission).

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D. C. Gold, P. Huft, C. Young, A. Safari, T. G. Walker, M. Saffman, D. D. Yavuz. 2021-12-14. Spatial Coherence of Light in Collective Spontaneous Emission. https://doi.org/10.1103/prxquantum.3.010338

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