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DOE OSTI · 2969874

Role of Matter Interactions in Superradiant Phenomena

Mendonça, João Pedro [Univ. of Warsaw (Poland)] (ORCID:0000000277659677)·Jachymski, Krzysztof [Univ. of Warsaw (Poland)] (ORCID:0000000290800989)·Wang, Yao [Emory Univ., Atlanta, GA (United States)] (ORCID:0000000317360187)
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Abstract

The superradiant phenomenon, usually described by the Dicke model, is a hallmark of strong light-matter interaction. Here, we explore how matter-matter interactions influence this phenomenon by performing ground-state simulations of Dicke-like models with both isotropic and anisotropic interactions. We find that Ising-type interactions produce two qualitatively distinct phase boundaries, one of which gives rise to an antiferromagnetic-normal phase connected to the superradiant regime via a first-order phase transition. Under anisotropic couplings, we uncover a strongly correlated phase where in-plane spin order coexists with superradiance, exhibiting sublinear scaling of the photon occupation per site and power-law decay of spin correlations. Furthermore, superradiance is strengthened by tuning either isotropic or anisotropic interactions, highlighting the role of intrinsic many-body correlations in shaping light-matter quantum phases.

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Dicke modelcavity quantum electrodynamicsphase transitionsquantum opticssubradiancesuperradiance

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Mendonça, João Pedro [Univ. of Warsaw (Poland)] (ORCID:0000000277659677), Jachymski, Krzysztof [Univ. of Warsaw (Poland)] (ORCID:0000000290800989), Wang, Yao [Emory Univ., Atlanta, GA (United States)] (ORCID:0000000317360187). 2025-09-23. Role of Matter Interactions in Superradiant Phenomena. https://doi.org/10.1103/z8gv-7yyk

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