Excited-state quantum phase transitions. (16th March 2021)

• Record Type: Journal Article
• Authors: Cejnar, Pavel; Stránský, Pavel; Macek, Michal; Kloc, Michal
• Is Part Of: Journal of physics. Volume 54:Number 13(2021)
• Publication Date: 2021-03-16
• Subjects: collective and fully connected many-body systems -- infinite-size singularities of Hamiltonian eigenvalues and eigenvectors -- quasiclassical level density and level dynamics -- microcanonical phase transitions -- anomalous response to external driving -- tunneling singularities; Mathematical physics -- Periodicals; Statistical physics -- Periodicals; Quantum theory -- Periodicals; Matter -- Properties -- Periodicals; 530.105
• DOI: 10.1088/1751-8121/abdfe8
• Languages: English
• ISSNs: 1751-8113

Abstract

Abstract: We review the effects of excited-state quantum phase transitions (ESQPTs) in interacting many-body systems with finite numbers of collective degrees of freedom. We classify typical ESQPT signatures in the spectra of energy eigenstates with respect to the underlying classical dynamics and outline a variety of quantum systems in which they occur. We describe thermodynamic and dynamic consequences of ESQPTs, like those in microcanonical thermodynamics, quantum quench dynamics, and in the response to nearly adiabatic or periodic driving. We hint at some generalizations of the ESQPT concept in periodic lattices and in resonant tunneling systems.