SciPost Submission Page
Spin-chain based quantum thermal machines
by Edoardo Maria Centamori, Michele Campisi, Vittorio Giovannetti
Submission summary
| Authors (as registered SciPost users): | Michele Campisi · Vittorio Giovannetti |
| Submission information | |
|---|---|
| Preprint Link: | scipost_202403_00002v1 (pdf) |
| Date submitted: | 2024-03-01 22:27 |
| Submitted by: | Giovannetti, Vittorio |
| Submitted to: | SciPost Physics |
| Ontological classification | |
|---|---|
| Academic field: | Physics |
| Specialties: |
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| Approach: | Theoretical |
Abstract
We study the performance of quantum thermal machines in which the working fluid of the model is represented by a many-body quantum system that is periodically connected with external baths via local couplings. A formal characterization of the limit cycles of the set-up is presented in terms of the mixing properties of the quantum channel that describes the evolution of the fluid over a thermodynamic cycle. For the special case in which the system is a collection of spin 1/2 particles coupled via magnetization preserving Hamiltonians, a full characterization of the possible operational regimes (i.e., thermal engine, refrigerator, heater and thermal accelerator) is provided: in this context we show in fact that the different regimes only depend upon a limited number of parameters (essentially the ratios of the energy gaps associated with the local Hamiltonians of the parts of the network which are in direct thermal contact with the baths).
Author comments upon resubmission
We would like to thank you and the referees for reviewing our work titled:
Spin-chain based quantum thermal machines
The referees raised a number of pertinent questions which we all addressed below in our replies, and implemented in the manuscript. Amendments include added text, modified text, improved figures, references added, minor typos corrected. Our replies below are in blue and the text changes are highlighted in red for your convenience.
We think that this new version now meets the publication criteria of SciPost and hope to see our work soon disseminated through it.
Sincerely,
Vittorio Giovannetti, Michele Campisi, Edoardo Maria Centamori
List of changes
We have modified the paper following the referee suggestions. In particular
1) a sentence has been added in the introductory section to specify what type of external driving we use in the protocol
2) The introductory part of Sec. II A has been re-edited to improve the presentation of how the LCPTP formalism is used in the analysis.
3) A sentence has been modified in Sec. II B to improve the presentation of the mixing property of LCPTP maps.
4) A new section has been added at the end of Sec. III B to better explain the low-temperature analysis of the model.
5) A new sentence has been added at the end of the conclusions.
6) The quality of the figures has been improved following the suggestions of the referee.
7) Minor editing and typos corrections.
Current status:
Reports on this Submission
Report
I am happy with the changes made by the authors. I recommend publication in SciPost physics if the changes below are addressed.
Requested changes
1. It occurred to me on a second reading that, although the validity of Eq 49 for larger spin chains is asserted, no explicit numerical evidence for this is given. Could this be included? (For example, one could plot Qh and Qc as a function of tau for different temperatures and show that the curves are universal when divided by g (Eq 50).)
2. It may be good to state the values of tau used for Fig 2, for reproducibility.
3. There are some other works on spin chain engines that the authors may wish to reference, for example Phys. Rev. Research 2, 043247 (2020), Phys. Rev. E 102, 012138 (2020), Phys. Rev. Research 2, 023145 (2020), Phys. Rev. B 109, 024310 (2024).
Report
The authors have considered and addressed satisfactorily all the points raised in the referee report.
The only thing is that I could not see footnote [42] in the pdf file I had access to, however I agree with what the authors have written in the reply to my comments/questions. So I think that the paper is ready for publication.