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arXiv · 2105.01080

Tunable Feshbach resonances and their spectral signatures in bilayer semiconductors

Clemens Kuhlenkamp·Michael Knap·Marcel Wagner·Richard Schmidt·Atac Imamoglu
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Abstract

Feshbach resonances are an invaluable tool in atomic physics, enabling precise control of interactions and the preparation of complex quantum phases of matter. Here, we theoretically analyze a solid-state analogue of a Feshbach resonance in two dimensional semiconductor heterostructures. In the presence of inter-layer electron tunneling, the scattering of excitons and electrons occupying different layers can be resonantly enhanced by tuning an applied electric field. The emergence of an inter-layer Feshbach molecule modifies the optical excitation spectrum, and can be understood in terms of Fermi polaron formation. We discuss potential implications for the realization of correlated Bose-Fermi mixtures in bilayer semiconductors.

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Clemens Kuhlenkamp, Michael Knap, Marcel Wagner, Richard Schmidt, Atac Imamoglu. 2021-05-03. Tunable Feshbach resonances and their spectral signatures in bilayer semiconductors. https://doi.org/10.1103/physrevlett.129.037401

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