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Iterative procedure for computing accessible information in quantum communication

Jaroslav Řeháček·Berthold-Georg Englert·Dagomir Kaszlikowski
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Abstract

We present an iterative algorithm that finds the optimal measurement for extracting the accessible information in any quantum communication scenario. The maximization is achieved by a steepest-ascent approach toward the extremal point, following the gradient uphill in sufficiently small steps. We apply it to a simple ad-hoc example, as well as to a problem with a bearing on the security of a tomographic protocol for quantum key distribution.

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Jaroslav Řeháček, Berthold-Georg Englert, Dagomir Kaszlikowski. 2004-08-20. Iterative procedure for computing accessible information in quantum communication. https://doi.org/10.1103/physreva.71.054303

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