Verification of the quantum nonequilibrium work relation in the presence of decoherence

Abstract

Although nonequilibrium work and fluctuation relations have been studied in\ndetail within classical statistical physics, extending these results to open\nquantum systems has proven to be conceptually difficult. For systems that\nundergo decoherence but not dissipation, we argue that it is natural to define\nquantum work exactly as for isolated quantum systems, using the two-point\nmeasurement protocol. Complementing previous theoretical analysis using quantum\nchannels, we show that the nonequilibrium work relation remains valid in this\nsituation, and we test this assertion experimentally using a system engineered\nfrom an optically trapped ion. Our experimental results reveal the work\nrelation's validity over a variety of driving speeds, decoherence rates, and\neffective temperatures and represent the first confirmation of the work\nrelation for non-unitary dynamics.\n