arXiv:2306.09578

Detailed Fluctuation Theorem from the One-Time Measurement Scheme

Maeda, Kenji, Tharon Holdsworth, Sebastian Deffner, Akira Sone

Published Jun 16, 2023• 0 citations

Abstract

The quantum fluctuation theorem can be regarded as the first principle of quantum nonequilibrium thermodynamics. However, many different formulations have been proposed, which depend on how quantum work is defined. In this context, we have seen that for some situations the one-time measurement (OTM) scheme can be more informative than the two-time measurement (TTM) scheme. Yet, so far the focus of OTM has been on integral fluctuation theorems, since, the work distribution of the backward process has been lacking. To this end, we prove that the OTM scheme is the nondestructive TTM scheme, in which the final state is a pointer state of the second measurement whose Hamiltonian is conditioned on the first measurement outcome. This insight leads to a derivation of the detailed fluctuation theorem for the characteristic functions of the forward and backward work distributions. Finally, our conceptual findings are experimentally verified with the IBM quantum computer.

DOI: 10.13016/m2aqvs-i8y0

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