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arXiv:1610.02697 · Physical review. B./Physical review. B

Analysis of the conditional average and conditional variance of dissipated energy in the driven spin-boson model

Philip Wollfarth, Yasuhiro Utsumi, Alexander Shnirman

Published Aug 7, 2017• 3 citations
arXivHTMLPDF

Abstract

We investigate the conditional average and the conditional variance of dissipated energy considering, as a prototypical example, a driven spin-boson system. We follow a measurement protocol in which the spin is prepared in a certain initial state before undergoing a periodic driving. Subsequently, the spin is projected onto a postselected final state. We compare the conditional average of dissipated energy to the lower bound, which directly follows from the well-known fluctuation relations. We further report that a special selection of the initial (preselected) and final (postselected) spin states leads to an enhanced energy emission with simultaneous noise suppression at driving times of order of the relaxation time.

DOI
10.1103/physrevb.96.064302

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