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arXiv · 1705.04223

Lower bounds on distances between a given quantum channel and certain classes of channels

M. E. Shirokov·A. V. Bulinski
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Abstract

The tight, in a sense, lower estimates of diamond-norm distance from a given quantum channel to the sets of degradable, antidegradable and entanglement-breaking channels are obtained via the tight continuity bounds for quantum mutual information and for relative entropy of entanglement in finite-dimensional case. As an auxiliary result there are established lower bounds of trace-norm distance from a given bipartite state to the set of all separable states.

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M. E. Shirokov, A. V. Bulinski. 2017-05-11. Lower bounds on distances between a given quantum channel and certain classes of channels. https://doi.org/10.1007/s10958-019-04419-2

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