Abstract
We derive the extended entanglement entropy and the Fisher information metric in the case of quantum models, described by time-independent diagonal quadratic Hamiltonians. Our research is conducted within the framework of Thermo field dynamics. We also study the properties of the Fisher metric invariants to identify the phase structure of the quasi-particle systems in equilibrium.
Information
Published: 1 January 2018
First available in Project Euclid: 23 December 2017
MathSciNet: MR3586171
Digital Object Identifier: 10.7546/giq-19-2018-225-233
Rights: Copyright © 2018 Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences