Bridging the gap between topological non-Hermitian physics and open quantum systems
Quantum Physics
2022-07-27 v1 Mesoscale and Nanoscale Physics
Optics
Abstract
We relate topological properties of non-Hermitian systems and observables of quantum open systems by using the Keldysh path-integral method. We express Keldysh Green's functions in terms of effective non-Hermitian Hamiltonians that contain all the relevant topological information. We arrive at a frequency dependent topological index that is linked to the response of the system to perturbations at a given frequency. We show how to detect a transition between different topological phases by measuring the response to local perturbations. Our formalism is exemplified in a 1D Hatano-Nelson model, highlighting the difference between the bosonic and fermionic cases
Keywords
Cite
@article{arxiv.2109.10930,
title = {Bridging the gap between topological non-Hermitian physics and open quantum systems},
author = {Álvaro Gómez-León and Tomás Ramos and Alejandro González-Tudela and Diego Porras},
journal= {arXiv preprint arXiv:2109.10930},
year = {2022}
}
Comments
5 pages, 3 figures and Appendix