Hierarchic superradiant phases in anisotropic Dicke model, by DaKai He, Zhi Song

SciPost Physics Core Home Authoring Refereeing Submit a manuscript About Hierarchic superradiant phases in anisotropic Dicke model DaKai He, Zhi Song SciPost Phys. Core 9, 009 (2026) · published 11 February 2026 doi: 10.21468/SciPostPhysCore.9.1.009 pdf BiBTeX RIS Submissions/Reports Abstract We revisit the phase diagram of an anisotropic Dicke model by revealing the non-analyticity induced by underlying exceptional points. We find that, from a dynamical perspective, the conventional superradiant phase can be further separated into three regions, in which the systems are characterized by different effective Hamiltonians, including the harmonic oscillator, the inverted harmonic oscillator, and their respective counterparts. We employ the Loschmidt echo to characterize different quantum phases by analyzing the quench dynamics of a trivial initial state. Numerical simulations for finite systems confirm our predictions about the existence of hierarchic superradiant phases. × TY - JOURPB - SciPost FoundationDO - 10.21468/SciPostPhysCore.9.1.009TI - Hierarchic superradiant phases in anisotropic Dicke modelPY - 2026/02/11UR - https://scipost.org/SciPostPhysCore.9.1.009JF - SciPost Physics CoreJA - SciPost Phys. CoreVL - 9IS - 1SP - 009A1 - He, DaKaiAU - Song, ZhiAB - We revisit the phase diagram of an anisotropic Dicke model by revealing the non-analyticity induced by underlying exceptional points. We find that, from a dynamical perspective, the conventional superradiant phase can be further separated into three regions, in which the systems are characterized by different effective Hamiltonians, including the harmonic oscillator, the inverted harmonic oscillator, and their respective counterparts. We employ the Loschmidt echo to characterize different quantum phases by analyzing the quench dynamics of a trivial initial state. Numerical simulations for finite systems confirm our predictions about the existence of hierarchic superradiant phases.ER - × @Article{10.21468/SciPostPhysCore.9.1.009, title={{Hierarchic superradiant phases in anisotropic Dicke model}}, author={DaKai He and Zhi Song}, journal={SciPost Phys. Core}, volume={9}, pages={009}, year={2026}, publisher={SciPost}, doi={10.21468/SciPostPhysCore.9.1.009}, url={https://scipost.org/10.21468/SciPostPhysCore.9.1.009},} Ontology / Topics See full Ontology or Topics database. Dicke model Dynamical phase transitions Exact diagonalization Quantum phase transitions Authors / Affiliation: mappings to Contributors and Organizations See all Organizations. 1 DaKai He, 1 Zhi Song 1 南开大学 / Nankai University [NKU] Funder for the research work leading to this publication National Natural Science Foundation of China [NSFC]