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arXiv · 1902.05801

Mean-field phase diagram of ultracold atomic gases in cavity quantum electrodynamics

Lukas Himbert·Cecilia Cormick·Rebecca Kraus·Shraddha Sharma·Giovanna Morigi
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Abstract

We investigate the mean-field phase diagram of the Bose-Hubbard model with infinite-range interactions in two dimensions. This model describes ultracold bosonic atoms confined by a two-dimensional optical lattice and dispersively coupled to a cavity mode with the same wavelength as the lattice. We determine the ground-state phase diagram for a grand-canonical ensemble by means of analytical and numerical methods. Our results mostly agree with the ones reported in Dogra et al. [PRA 94, 023632 (2016)], and have a remarkable qualitative agreement with the quantum Monte Carlo phase diagrams of Flottat et al. [PRB 95, 144501 (2017)]. The salient differences concern the stability of the supersolid phases, which we discuss in detail. Finally, we discuss differences and analogies between the ground state properties of strong long-range interacting bosons with the ones predicted for repulsively interacting dipolar bosons in two dimensions.

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Lukas Himbert, Cecilia Cormick, Rebecca Kraus, Shraddha Sharma, Giovanna Morigi. 2019-02-15. Mean-field phase diagram of ultracold atomic gases in cavity quantum electrodynamics. https://doi.org/10.1103/physreva.99.043633

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