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arXiv · 1207.2978

Holevo's bound from a general quantum fluctuation theorem

Dvir Kafri·Sebastian Deffner
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Abstract

We give a novel derivation of Holevo's bound using an important result from nonequilibrium statistical physics, the fluctuation theorem. To do so we develop a general formalism of quantum fluctuation theorems for two-time measurements, which explicitly accounts for the back action of quantum measurements as well as possibly non-unitary time evolution. For a specific choice of observables this fluctuation theorem yields a measurement-dependent correction to the Holevo bound, leading to a tighter inequality. We conclude by analyzing equality conditions for the improved bound.

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Dvir Kafri, Sebastian Deffner. 2012-10-05. Holevo's bound from a general quantum fluctuation theorem. https://doi.org/10.1103/physreva.86.044302

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