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arXiv · 1207.3053

Direct estimation of decoherence rates

Vladimír Bužek·Peter Rapcan·Jochen Rau·Mario Ziman
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Abstract

The decoherence rate is a nonlinear channel parameter that describes quantitatively the decay of the off-diagonal elements of a density operator in the decoherence basis. We address the question of how to experimentally access such a nonlinear parameter directly without the need of complete process tomography. In particular, we design a simple experiment working with two copies of the channel, in which the registered mean value of a two-valued measurement directly determines the value of the average decoherence rate. No prior knowledge of the decoherence basis is required.

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Vladimír Bužek, Peter Rapcan, Jochen Rau, Mario Ziman. 2012-07-30. Direct estimation of decoherence rates. https://doi.org/10.1103/physreva.86.052109

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