Uhlmann number in translational invariant systems
Quantum Physics
2019-06-26 v3 Statistical Mechanics
Strongly Correlated Electrons
Abstract
We define the Uhlmann number as an extension of the Chern number, and we use this quantity to describe the topology of 2D translational invariant Fermionic systems at finite temperature. We consider two paradigmatic systems and we study the changes in their topology through the Uhlmann number. Through the linear response theory we linked two geometrical quantities of the system, the mean Uhlmann curvature and the Uhlmann number, to directly measurable physical quantities, i.e. the dynamical susceptibility and to the dynamical conductivity, respectively.
Keywords
Cite
@article{arxiv.1806.08592,
title = {Uhlmann number in translational invariant systems},
author = {Luca Leonforte and Davide Valenti and Bernardo Spagnolo and Angelo Carollo},
journal= {arXiv preprint arXiv:1806.08592},
year = {2019}
}
Comments
5 pages, 3 figures