Concurrence of Stochastic 1-Qubit Maps

Abstract

Explicit expressions for the concurrence of all positive and trace-preserving ("stochastic") 1-qubit maps are presented. By a new method we find the relevant convex roof pattern. We conclude that two component optimal decompositions always exist. Our results can be transferred to $2\times n$-quantum systems providing the concurrence for all rank two density operators as well as a lower bound for their entanglement of formation.

longer intro, small changes in text

Cited by in corpus (1)

• Concurrence and Entanglement Entropy of Stochastic 1-Qubit Maps