AIP conference proceedings

Quantum phase transitions and excited-state scaling in bosonic and fermionic pairing models

M. A. Caprio

Published Jan 1, 2019• 1 citation

Abstract

A quantum phase transition (QPT) is a point of singularity in the evolution of the ground state properties as a function of pairing strength. However, a QPT may also be reflected in the properties of excited states and the nature of the low-lying excitation spectrum. This contribution examines excited-state scaling properties in the vicinity of the QPT for bosonic and fermionic two-level pairing models. It is found that the numerically-determined power laws for the excited-state scaling properties can be understood in terms of a simple semiclassical description.

DOI: 10.1063/1.5124588

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