2015/04/30 by Jochen Gemmer, J. Gemmer, Janet Anders +1 · 2 citations
Physics and Astronomy · #Advanced Thermodynamics and Statistical Mechanics #Energy (signal processing) #Extension (predicate logic) #Quantum #Quantum many-body systems #Single level #Single shot #Spectroscopy and Quantum Chemical Studies #Subspace topology #Thermal #Work (physics) #cond-mat.stat-mech #quant-ph
paper · pdf · doi:10.1088/1367-2630/17/8/085006
published as New J. Phys. 17 085006 (2015) · 3 figures, added a discussion of bringing in new baths, minor changes throughout, accepted in NJP
arxiv created 2015/06/30 · openalex publication_date 2015/08/18 · arxiv updated 2016/04/07 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/06
This paper considers work extraction from a quantum system to a work storage system (or weight) following Horodecki and Oppenheim (2013 Nat. Commun. 4 2059 ). An alternative approach is here developed that relies on the comparison of subspace dimensions without a need to introduce thermo-majorization used previously. Optimal single shot work for processes where a weight transfers from (a) a single energy level to another single energy level is then re-derived. In addition we discuss the final state of the system after work extraction and show that the system typically ends in its thermal state, while there are cases where the system is only close to it. The work of formation in the single level transfer setting is also re-derived. The approach presented now allows the extension of the single shot work concept to work extraction (b) involving multiple final levels of the weight. A key conclusion here is that the single shot work for case (a) is appropriate only when a resonance of a particular energy is required. When wishing to identify 'work extraction' with finding the weight in a specific available energy or any higher energy a broadening of the single shot work concept is required. As a final contribution we consider transformations of the system that (c) result in general weight state transfers. Introducing a transfer-quantity allows us to formulate minimum requirements for transformations to be at all possible in a thermodynamic framework. We show that choosing the free energy difference of the weight as the transfer-quantity one recovers various single shot results including single level transitions (a), multiple final level transitions (b), and recent results on restricted sets of multi-level to multi-level weight transfers.