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Journal de Physique I

Fluctuation theory for an equilibrium superradiant model

Maria Adamuti‐Trache

Published Apr 1, 1993• 1 citation
Publisher

Abstract

Some critical properties for static and dynamic equilibrium superradiant models are discussed, within a Gaussian fluctuation theory. The temperature critical region and the λ-critical region are calculated and the phase diagram of the superradiant phase transition is obtained.
DOI
10.1051/jp1:1993177

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Various light-matter interactions lead to diverse phase diagram structures in superradiant phase transition (SPT) studies. Such systems consist of multiqubit and multimode with anisotropic couplings, one- and two-photon interactions, Stark shifts, inter-cavity hoppings, qubit-qubit interactions and so on. We find a general phase diagram feature that the origin is in normal phase (NP) and SPT happens only once along the radial direction of a chosen coupling parameter vector with the mean-field method at finite temperature. We can calculate the phase boundary and SPT properties by a concise method. We illustrate it with specific models and find SPT can be achieved in strong coupling regime by means of multimode collective behavior. We also find the disorder will shift the phase boundary. These general features facilitate SPT studies and their diverse applications.
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