Exact non-equilibrium quantum observable statistics.

Stefano Gherardini

Published Jan 31, 2019• 0 citations

Abstract

The exact statistics of an arbitrary measuring observable, describing specific features of an open quantum system, is analytically obtained. Due to the probabilistic nature of a sequence of intermediate measurements and stochastic fluctuations induced by the interaction with an external environment, the measurement outcomes at the end of the system evolution are random variables. Here, we provide the exact large deviation form of their probability distribution, given by an exponentially decaying profile in the number of measurements. The most probable distribution of the measurement outcomes in a single realization of the system transformation is then derived, thus achieving predictions beyond the expectation value.

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