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arXiv · 2305.11610

Fermionic matter-wave quantum optics with cold-atom impurity models

Bennet Windt·Miguel Bello·Eugene Demler·J. Ignacio Cirac
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Abstract

Motivated by recent cold-atom realisations of matter-wave waveguide QED, we study simple fermionic impurity models and discuss fermionic analogues of several paradigmatic phenomena in quantum optics, including formation of non-trivial bound states, (matter-wave) emission dynamics, and collective dissipation. For a single impurity, we highlight interesting ground-state features, focusing in particular on real-space signatures of an emergent length scale associated with an impurity screening cloud. We also present novel non-Markovian many-body effects in the quench dynamics of single- and multiple-impurity systems, including fractional decay around the Fermi level and multi-excitation population trapping due to bound states in the continuum.

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Bennet Windt, Miguel Bello, Eugene Demler, J. Ignacio Cirac. 2023-05-19. Fermionic matter-wave quantum optics with cold-atom impurity models. https://doi.org/10.1103/physreva.109.023306

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