Related papers: Bridging the gap between topological non-Hermitian physics and open quantum systems

Bridging the gap between topological non-Hermitian physics and open quantum systems

URL: http://arxiv.org/abs/2109.10930v1
Date: Wed, 22 Sep 2021 18:00:17 GMT
Title: Bridging the gap between topological non-Hermitian physics and open quantum systems
Authors: \'Alvaro G\'omez-Le\'on, Tom\'as Ramos, Alejandro Gonz\'alez-Tudela, Diego Porras
Abstract summary: 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.
Score: 62.997667081978825
License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
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

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