Yunger Halpern, N;
Faist, P;
Oppenheim, J;
Winter, A;
(2016)
Microcanonical and resource-theoretic derivations of the thermal state of a quantum system with noncommuting charges.
Nature Communications
, 7
, Article 12051. 10.1038/ncomms12051.
Preview |
Text
ncomms12051.pdf - Published Version Download (455kB) | Preview |
Abstract
The grand canonical ensemble lies at the core of quantum and classical statistical mechanics. A small system thermalizes to this ensemble while exchanging heat and particles with a bath. A quantum system may exchange quantities represented by operators that fail to commute. Whether such a system thermalizes and what form the thermal state has are questions about truly quantum thermodynamics. Here we investigate this thermal state from three perspectives. First, we introduce an approximate microcanonical ensemble. If this ensemble characterizes the system-and-bath composite, tracing out the bath yields the system’s thermal state. This state is expected to be the equilibrium point, we argue, of typical dynamics. Finally, we define a resource-theory model for thermodynamic exchanges of noncommuting observables. Complete passivity—the inability to extract work from equilibrium states—implies the thermal state’s form, too. Our work opens new avenues into equilibrium in the presence of quantum noncommutation.
| Type: | Article |
|---|---|
| Title: | Microcanonical and resource-theoretic derivations of the thermal state of a quantum system with noncommuting charges |
| Open access status: | An open access version is available from UCL Discovery |
| DOI: | 10.1038/ncomms12051 |
| Publisher version: | http://dx.doi.org/10.1038/ncomms12051 |
| Language: | English |
| Additional information: | This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/ |
| 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-pp.ucl.ac.uk/id/eprint/1518008 |
Archive Staff Only
 |
View Item |
