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arXiv · 1908.04844

Inelastic scattering of photon pairs in qubit arrays with subradiant states

Yongguan Ke·Alexander V. Poshakinskiy·Chaohong Lee·Yuri S. Kivshar·Alexander N. Poddubny
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Abstract

We develop a rigorous theoretical approach for analyzing inelastic scattering of photon pairs in arrays of two-level qubits embedded in a waveguide. Our analysis reveals strong enhancement of the scattering when the energy of incoming photons resonates with the double-excited subradiant states. We identify the role of different double-excited states in the scattering such as superradiant, subradiant, and twilight states, being a product of single-excitation bright and subradiant states. Importantly, the N-excitation subradiant states can be engineered only if the number of qubits exceeds 2N. Both the subradiant and twilight states can generate long-lived photon-photon correlations, paving the way to a storage and processing of quantum information.

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Yongguan Ke, Alexander V. Poshakinskiy, Chaohong Lee, Yuri S. Kivshar, Alexander N. Poddubny. 2019-11-13. Inelastic scattering of photon pairs in qubit arrays with subradiant states. https://doi.org/10.1103/physrevlett.123.253601

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