RT Journal Article
T1 Quantum collisional thermostats
A1 Tabanera Bravo, Jorge
A1 Luque, Inés
A1 Jacob, Samuel L
A1 Esposito, Massimiliano
A1 Barra, Felipe
A1 Rodríguez Parrondo, Juan Manuel
AB Collisional reservoirs are becoming a major tool for modelling open quantum systems. In their simplest implementation, an external agent switches on, for a given time, the interaction between the system and a specimen from the reservoir. Generically, in this operation the external agent performs work onto the system, preventing thermalization when the reservoir is at equilibrium. One can recover thermalization by considering an autonomous global setup where the reservoir particles colliding with the system possess a kinetic degree of freedom. The drawback is that the corresponding scattering problem is rather involved. Here, we present a formal solution of the problem in one dimension and for flat interaction potentials. The solution is based on the transfer matrix formalism and allows one to explore the symmetries of the resulting scattering map. One of these symmetries is micro-reversibility, which is a condition for thermalization. We then introduce two approximations of the scattering map that preserve these symmetries and, consequently, thermalize the system. These relatively simple approximate solutions constitute models of quantum thermostats and are useful tools to study quantum systems in contact with thermal baths. We illustrate their accuracy in a specific example, showing that both are good approximations of the exact scattering problem even in situations far from equilibrium. Moreover, one of the models consists of the removal of certain coherences plus a very specific randomization of the interaction time. These two features allow one to identify as heat the energy transfer due to switching on and off the interaction. Our results prompt the fundamental question of how to distinguish between heat and work from the statistical properties of the exchange of energy between a system and its surroundings.
PB IOP Publishing
SN 1367-2630
YR 2022
FD 2022-02-01
LK https://hdl.handle.net/20.500.14352/71461
UL https://hdl.handle.net/20.500.14352/71461
LA eng
NO SLJ is supported by the Doctoral Training Unit on Materials for Sensing and Energy Harvesting (MASSENA) with the Grant: FNR PRIDE/15/10935404. ME acknowledges financial support from the European Research Council (project NanoThermo, ERC-2015-CoG Agreement No. 681456) and the FQXi foundation, project 'Information as a fuel in colloids and superconducting quantum circuits' (FQXi-IAF19-05). FB thanks Fondecyt project 1191441 and the Millennium Nucleus 'Physics of active matter' of ANID (Chile). Part of this work was conducted at the KITP, a facility supported by the US National Science Foundation under Grant No. NSF PHY-1748958. JMRP, JT and IL acknowledge financial support from the Spanish Government (Grant Contracts FIS-2017-83706-R and PID2020-113455GB-I00) and from the Foundational Questions Institute Fund, a donor advised fund of Silicon Valley Community Foundation (Grant Number FQXi-IAF19-01).
NO Unión Europea. Horizonte 2020
NO Ministerio de Ciencia e Innovación (MICINN)
NO Doctoral Training Unit on Materials for Sensing and Energy Harvesting (MASSENA)
NO FQXi foundation
NO Fondecyt Comisión Nacional de Investigación Científica y Tecnológica (CONICYT) CONICYT FONDECYT
NO Millennium Nucleus 'Physics of active matter' of ANID (Chile)
NO US National Science Foundation (NSF)
NO Foundational Questions Institute Fund, Silicon Valley Community Foundation
DS Docta Complutense
RD 12 may 2025