Decomposability and convex structure of thermal processes
Paweł Mazurek , Michał Horodecki
AbstractWepresent an example of a thermal process (TP) for a system of d energy levels,which cannot be performedwithout an instant access to thewhole energy space. This TPis uniquely connected with a transition between somestates of the system, that cannot be performed without access to thewhole energy space evenwhen approximate transitions are allowed. Pursuing the question about the decomposability of TPs into convex combinations of compositions of processes acting non-trivially on smaller subspaces,we investigate transitionswithin the subspace of states diagonal in the energy basis. For three level systems,we determine the set of extremal points of these operations, aswell as the minimal set of operations needed to perform an arbitrary TP, and connect the set of TPswith thermomajorization criterion.Weshow that the structure of the set depends on temperature, which is associatedwith the fact that TPs cannot increase deterministically extractablework from a state—the conclusion that holds for arbitrary d level system.We also connect the decomposability problemwith detailed balance symmetry of an extremalTPs.
|Journal series||New Journal of Physics, ISSN , e-ISSN 1367-2630, (A 40 pkt)|
|Publication size in sheets||0.7|
|Keywords in English||quantum thermodynamics, thermal process, thermal operation, convex set|
|License||Journal (articles only); published final; ; with publication|
|Score|| = 40.0, ArticleFromJournal|
= 40.0, ArticleFromJournal
|Publication indicators||: 2017 = 3.579 (2) - 2017=3.616 (5)|
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