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arXiv · 2203.00823

Nonreciprocal and chiral single-photon scattering for giant atoms

Yao-Tong Chen·Lei Du·Lingzhen Guo·Zhihai Wang·Yan Zhang·Yong Li·Jin-Hui Wu
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Abstract

Quantum optics with giant atoms has provided a new paradigm to study photon scatterings. In this work, we investigate the nontrivial single-photon scattering properties of giant atoms being an effective platform to realize nonreciprocal and chiral quantum optics. For two-level giant atoms, we identify the condition for nonreciprocal transmission: the external atomic dissipation is further required other than the breaking of time-reversal symmetry by local coupling phases. Especially, in the non-Markovian regime, unconventional revival peaks periodically appear in the reflection spectrum. To explore more interesting scattering behaviors, we extend the two-level giant-atom system to Δ-type and {\nabla}-type three-level giant atoms coupled to double waveguides with different physical mechanisms to realize nonreciprocal and chiral scatterings. Our proposed giant-atom structures have potential applications of high-efficiency targeted routers that can transport single photons to any desired port deterministically and circulators that can transport single photons between four ports in a cyclic way.

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Yao-Tong Chen, Lei Du, Lingzhen Guo, Zhihai Wang, Yan Zhang, Yong Li, Jin-Hui Wu. 2023-02-24. Nonreciprocal and chiral single-photon scattering for giant atoms. https://doi.org/10.1038/s42005-022-00991-3

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