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arXiv · 2011.14550

Two-photon superbunching effect of broadband chaotic stationary light at femtosecond timescale based on cascaded Michelson interferometer

Sheng Luo·Yu Zhou·Huaibin Zheng·Jianbin Liu·Hui Chen·Yuchen He·Wanting Xu·Shuanghao Zhang·Fuli Li·Zhuo Xu
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Abstract

It is challenging for observing superbunching effect with true chaotic light, here we propose and demonstrate a method to achieve superbunching effect of the degree of second-order coherence is 2.42 with broadband stationary chaotic light based on a cascaded Michelson interferometer (CMI), exceeding the theoretical upper limit of 2 for the two-photon bunching effect of chaotic light. The superbunching correlation peak is measured with an ultrafast two-photon absorption detector which the full width at half maximum reaches about 95 fs. Two-photon superbunching theory in a CMI is developed to interpret the effect and is in agreement with experimental results. The theory also predicts that the degree of second-order coherence can be much greater than $2$ if chaotic light propagates $N$ times in a CMI. Finally, a new type of weak signals detection setup which employs broadband chaotic light circulating in a CMI is proposed. Theoretically, it can increase the detection sensitivity of weak signals 79 times after the chaotic light circulating 100 times in the CMI.

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Sheng Luo, Yu Zhou, Huaibin Zheng, Jianbin Liu, Hui Chen, Yuchen He, Wanting Xu, Shuanghao Zhang, Fuli Li, Zhuo Xu. 2020-11-30. Two-photon superbunching effect of broadband chaotic stationary light at femtosecond timescale based on cascaded Michelson interferometer. https://doi.org/10.1103/physreva.103.013723

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