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arXiv · 2606.18756

Universal photon blockade via two-photon light-matter interaction at chiral exceptional points

Hai-Tao Dong·Meng-Long Song·Si-Yu Zhang·Xue-Ke Song·Liu Ye·Dong Wang
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Abstract

The photon blockade (PB) effect is a hallmark non-classical phenomenon in quantum optics and finds important applications for building quantum sources, while the control of PB by the non-Hermitian exceptional points remains largely unexplored. In this work, we theoretically investigate universal photon blockade in a microcavity harboring chiral exceptional points (CEPs) for building multiplexing quantum sources with nonreciprocal photon statistics. The results reveal that the presence of the CEPs leads to a stark contrast in the photon statistics of two whispering-gallery modes with opposite propagating directions. That is, one mode exhibits a strong PB effect while the other displays either sub-Poissonian or super-Poissonian distribution. Our findings thus may pave the way for advanced applications of photon blockade, and provide a theoretical foundation for the selective generation of single-photon and two-photon emission

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Hai-Tao Dong, Meng-Long Song, Si-Yu Zhang, Xue-Ke Song, Liu Ye, Dong Wang. 2026-06-17. Universal photon blockade via two-photon light-matter interaction at chiral exceptional points. https://arxiv.org/abs/2606.18756

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