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arXiv · 1203.5547

Physical transformations between quantum states

Zejun Huang·Chi-Kwong Li·Edward Poon·Nung-Sing Sze
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Abstract

Given two sets of quantum states {A_1, ..., A_k} and {B_1, ..., B_k}, represented as sets of density matrices, necessary and sufficient conditions are obtained for the existence of a physical transformation T, represented as a trace-preserving completely positive map, such that T(A_i) = B_i for i = 1, ..., k. General completely positive maps without the trace-preserving requirement, and unital completely positive maps transforming the states are also considered.

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Zejun Huang, Chi-Kwong Li, Edward Poon, Nung-Sing Sze. 2012-03-25. Physical transformations between quantum states. https://doi.org/10.1063/1.4755846

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