Heitmann, T;
Richter, J;
Gemmer, J;
Steinigeweg, R;
(2021)
Nontrivial damping of quantum many-body dynamics.
Physical Review E
, 104
, Article 054145. 10.1103/PhysRevE.104.054145.
Preview |
Text
PhysRevE.104.054145.pdf - Published Version Download (1MB) | Preview |
Abstract
Understanding how the dynamics of a given quantum system with many degrees of freedom is altered by the presence of a generic perturbation is a notoriously difficult question. Recent works predict that, in the overwhelming majority of cases, the unperturbed dynamics is just damped by a simple function, e.g., exponentially as expected from Fermi's golden rule. While these predictions rely on random-matrix arguments and typicality, they can only be verified for a specific physical situation by comparing to the actual solution or measurement. Crucially, it also remains unclear how frequent and under which conditions counterexamples to the typical behavior occur. In this work, we discuss this question from the perspective of projection-operator techniques, where exponential damping of a density matrix occurs in the interaction picture but not necessarily in the Schr\"odinger picture. We show that a nontrivial damping in the Schr\"odinger picture can emerge if the dynamics in the unperturbed system possesses rich features, for instance due to the presence of strong interactions. This suggestion has consequences for the time dependence of correlation functions. We substantiate our theoretical arguments by large-scale numerical simulations of charge transport in the extended Fermi-Hubbard chain, where the nearest-neighbor interactions are treated as a perturbation to the integrable reference system.
| Type: | Article |
|---|---|
| Title: | Nontrivial damping of quantum many-body dynamics |
| Open access status: | An open access version is available from UCL Discovery |
| DOI: | 10.1103/PhysRevE.104.054145 |
| Publisher version: | http://dx.doi.org/10.1103/PhysRevE.104.054145 |
| Language: | English |
| Additional information: | This version is the version of record. For information on re-use, please refer to the publisher’s terms and conditions. |
| Keywords: | cond-mat.stat-mech, cond-mat.stat-mech, cond-mat.str-el, quant-ph |
| UCL classification: | UCL UCL > Provost and Vice Provost Offices > UCL BEAMS UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences > Dept of Physics and Astronomy |
| URI: | https://discovery.ucl.ac.uk/id/eprint/10140082 |
Loading...
Loading...Loading...Loading...Archive Staff Only
 |
View Item |
