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arXiv · 2212.06307

Non-Hermitian Anharmonicity Induces Single-Photon Emission

Anael Ben-Asher·Antonio I. Fernández-Domínguez·Johannes Feist
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Abstract

Single-photon sources are in high demand for quantum information applications. A paradigmatic way to achieve single-photon emission is through anharmonicity in the energy levels, such that the absorption of a single photon from a coherent drive shifts the system out of resonance and prevents absorption of a second one. We identify a novel mechanism for single-photon emission through non-Hermitian anharmonicity, i.e., anharmonicity in the losses instead of in the energy levels. We demonstrate the mechanism in two types of systems, including a feasible setup consisting of a hybrid metallodielectric cavity weakly coupled to a two-level emitter, and show that it induces high-purity single-photon emission at high repetition rates.

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Anael Ben-Asher, Antonio I. Fernández-Domínguez, Johannes Feist. 2022-12-13. Non-Hermitian Anharmonicity Induces Single-Photon Emission. https://doi.org/10.1103/physrevlett.130.243601

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