Quantum quenches in driven-dissipative quadratic fermionic systems with parity-time symmetry

We study the quench dynamics of noninteracting fermionic quantum many-body systems that are subjected to Markovian drive and dissipation and are described by a quadratic Liouvillian which has parity-time (PT) symmetry. In recent work, we have shown that such systems relax locally to a maximum entrop...

Full description

Bibliographic Details
Main Authors: Elias Starchl, Lukas M. Sieberer
Format: Article
Language:English
Published: American Physical Society 2024-01-01
Series:Physical Review Research
Online Access:http://doi.org/10.1103/PhysRevResearch.6.013016
_version_ 1797210343434354688
author Elias Starchl
Lukas M. Sieberer
author_facet Elias Starchl
Lukas M. Sieberer
author_sort Elias Starchl
collection DOAJ
description We study the quench dynamics of noninteracting fermionic quantum many-body systems that are subjected to Markovian drive and dissipation and are described by a quadratic Liouvillian which has parity-time (PT) symmetry. In recent work, we have shown that such systems relax locally to a maximum entropy ensemble that we have dubbed the PT-symmetric generalized Gibbs ensemble (PTGGE), in analogy to the generalized Gibbs ensemble that describes the steady state of isolated integrable quantum many-body systems after a quench. Here, using driven-dissipative versions of the Su-Schrieffer-Heeger (SSH) model and the Kitaev chain as paradigmatic model systems, we corroborate and substantially expand upon our previous results. In particular, we confirm the validity of a dissipative quasiparticle picture at finite dissipation by demonstrating light cone spreading of correlations and the linear growth and saturation to the PTGGE prediction of the quasiparticle-pair contribution to the subsystem entropy in the PT-symmetric phase. Further, we introduce the concept of directional pumping phases, which is related to the non-Hermitian topology of the Liouvillian and based upon qualitatively different dynamics of the dual string order parameter and the subsystem fermion parity in the SSH model and the Kitaev chain, respectively: depending on the postquench parameters, there can be pumping of string order and fermion parity through both ends of a subsystem corresponding to a finite segment of the one-dimensional lattice, through only one end, or there can be no pumping at all. We show that transitions between dynamical pumping phases give rise to a new and independent type of dynamical critical behavior of the rates of directional pumping, which are determined by the soft modes of the PTGGE.
first_indexed 2024-04-24T10:09:05Z
format Article
id doaj.art-e7651eda74344ff1975b28d480aa7544
institution Directory Open Access Journal
issn 2643-1564
language English
last_indexed 2024-04-24T10:09:05Z
publishDate 2024-01-01
publisher American Physical Society
record_format Article
series Physical Review Research
spelling doaj.art-e7651eda74344ff1975b28d480aa75442024-04-12T17:37:41ZengAmerican Physical SocietyPhysical Review Research2643-15642024-01-016101301610.1103/PhysRevResearch.6.013016Quantum quenches in driven-dissipative quadratic fermionic systems with parity-time symmetryElias StarchlLukas M. SiebererWe study the quench dynamics of noninteracting fermionic quantum many-body systems that are subjected to Markovian drive and dissipation and are described by a quadratic Liouvillian which has parity-time (PT) symmetry. In recent work, we have shown that such systems relax locally to a maximum entropy ensemble that we have dubbed the PT-symmetric generalized Gibbs ensemble (PTGGE), in analogy to the generalized Gibbs ensemble that describes the steady state of isolated integrable quantum many-body systems after a quench. Here, using driven-dissipative versions of the Su-Schrieffer-Heeger (SSH) model and the Kitaev chain as paradigmatic model systems, we corroborate and substantially expand upon our previous results. In particular, we confirm the validity of a dissipative quasiparticle picture at finite dissipation by demonstrating light cone spreading of correlations and the linear growth and saturation to the PTGGE prediction of the quasiparticle-pair contribution to the subsystem entropy in the PT-symmetric phase. Further, we introduce the concept of directional pumping phases, which is related to the non-Hermitian topology of the Liouvillian and based upon qualitatively different dynamics of the dual string order parameter and the subsystem fermion parity in the SSH model and the Kitaev chain, respectively: depending on the postquench parameters, there can be pumping of string order and fermion parity through both ends of a subsystem corresponding to a finite segment of the one-dimensional lattice, through only one end, or there can be no pumping at all. We show that transitions between dynamical pumping phases give rise to a new and independent type of dynamical critical behavior of the rates of directional pumping, which are determined by the soft modes of the PTGGE.http://doi.org/10.1103/PhysRevResearch.6.013016
spellingShingle Elias Starchl
Lukas M. Sieberer
Quantum quenches in driven-dissipative quadratic fermionic systems with parity-time symmetry
Physical Review Research
title Quantum quenches in driven-dissipative quadratic fermionic systems with parity-time symmetry
title_full Quantum quenches in driven-dissipative quadratic fermionic systems with parity-time symmetry
title_fullStr Quantum quenches in driven-dissipative quadratic fermionic systems with parity-time symmetry
title_full_unstemmed Quantum quenches in driven-dissipative quadratic fermionic systems with parity-time symmetry
title_short Quantum quenches in driven-dissipative quadratic fermionic systems with parity-time symmetry
title_sort quantum quenches in driven dissipative quadratic fermionic systems with parity time symmetry
url http://doi.org/10.1103/PhysRevResearch.6.013016
work_keys_str_mv AT eliasstarchl quantumquenchesindrivendissipativequadraticfermionicsystemswithparitytimesymmetry
AT lukasmsieberer quantumquenchesindrivendissipativequadraticfermionicsystemswithparitytimesymmetry