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Entanglement-assisted capacity of constrained quantum channel

A. S. Holevo
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Abstract

In this paper we fill the gap in previous works by proving the formula for entanglement-assisted capacity of quantum channel with additive constraint (such as bosonic Gaussian channel). The main tools are the coding theorem for classical-quantum constrained channels and a finite dimensional approximation of the input density operators for entanglement-assisted capacity. The new version contains improved formulation of sufficient conditions under which suprema in the capacity formulas are attained.

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A. S. Holevo. 2003-01-04. Entanglement-assisted capacity of constrained quantum channel. https://doi.org/10.1117/12.517873

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