| Full text | |
| Author(s): |
Serafini, A.
[1]
;
Lostaglio, M.
[2]
;
Longden, S.
[1]
;
Shackerley-Bennett, U.
[1]
;
Hsieh, C-Y
[2]
;
Adesso, G.
[3, 4]
Total Authors: 6
|
| Affiliation: | [1] UCL, Dept Phys & Astron, Gower St, London WC1E 6BT - England
[2] Barcelona Inst Sci & Technol, ICFO Inst Ciencies Foton, Castelldefels 08860 - Spain
[3] Univ Nottingham, Sch Math Sci, Univ Pk Campus, Nottingham NG7 2RD - England
[4] Univ Nottingham, Ctr Math & Theoret Phys Quantum Nonequilibrium Sy, Univ Pk Campus, Nottingham NG7 2RD - England
Total Affiliations: 4
|
| Document type: | Journal article |
| Source: | Physical Review Letters; v. 124, n. 1 JAN 2 2020. |
| Web of Science Citations: | 1 |
| Abstract | |
The study of thermal operations allows one to investigate the ultimate possibilities of quantum states and of nanoscale thermal machines. Whilst fairly general, these results typically do not apply to continuous variable systems and do not take into account that, in many practically relevant settings, system-environment interactions are effectively bilinear. Here we tackle these issues by focusing on Gaussian quantum states and channels. We provide a complete characterization of the most general Gaussian thermal operation acting on an arbitrary number of bosonic modes, which turn out to be all embeddable in a Markovian dynamics, and derive necessary and sufficient conditions for state transformations under such operations in the single-mode case, encompassing states with nonzero coherence in the energy eigenbasis (i.e., squeezed states). Our analysis leads to a no-go result for the technologically relevant task of algorithmic cooling: We show that it is impossible to reduce the entropy of a system coupled to a Gaussian environment below its own or the environmental temperature, by means of a sequence of Gaussian thermal operations interspersed by arbitrary (even non-Gaussian) unitaries. These findings establish fundamental constraints on the usefulness of Gaussian resources for quantum thermodynamic processes. (AU) | |
| FAPESP's process: | 17/07973-5 - Thermodynamics and information technologies with continuous variable quantum systems |
| Grantee: | Gabriel Teixeira Landi |
| Support Opportunities: | Regular Research Grants |