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arXiv · 1906.05104

Generating single longitudinal mode entangled photons in telecom band via a submillimeter monolithic cavity

Yin-Hai Li·Zhi-Yuan Zhou·Shi-Long Liu·Yan Li·Shi-Kai Liu·Chen Yang·Zhao-Huai Xu·Shuang Wang·Zhi-Han Zhu·Wei Gao·Guang-Can Guo·Bao-Sen Shi
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Abstract

A high-quality, compact, and narrow-bandwidth entangled photon source (EPS) is indispensable for realization of many quantum communication protocols. Usually, a free space cavity containing a nonlinear crystal is used to generate a narrow bandwidth EPS through spontaneous parametric down-conversion (SPDC). One major drawback is that this occupies a large space and requires complex optical and electrical control systems. Here we present a simple and compact method to generate a single-longitudinal-mode time-energy EPS via type II SPDC in a submillimeter Fabry-Perot cavity. We characterize the quality of the EPS by measuring the coincidence to accidental coincidence ratio, the two-photon time cross-correlation function and the two-photon interference fringes. All measured results clearly demonstrate that the developed source is of high quality when compared with EPSs generated using other configurations. We believe this source is very promising for applications in the quantum communication field.

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Yin-Hai Li, Zhi-Yuan Zhou, Shi-Long Liu, Yan Li, Shi-Kai Liu, Chen Yang, Zhao-Huai Xu, Shuang Wang, Zhi-Han Zhu, Wei Gao, Guang-Can Guo, Bao-Sen Shi. 2019-06-12. Generating single longitudinal mode entangled photons in telecom band via a submillimeter monolithic cavity. https://arxiv.org/abs/1906.05104

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