Journal of Shaanxi Normal University

Quantum correlation of a pair of quantum ensembles

Xueqi Cen

Published Jan 1, 2015• 0 citations

Abstract

Quantum correlation in a pair{e,η}of quantum ensembles is studied and computed.In quantum information theory,aquantum state of a quantum system lies in some stateρiat a certain probability pithrough a quantum measurement.Thus,quantum statesρ1,ρ2,…,ρnand corresponding probabilities p1,p2,…,pnare obtained and so an ensemblee={pi,ρi}ni=1is presented.To do this,a 4-partite quantum stateρe,ηis constructed,and based on quantum relative entropy,a measure function is defined in order to reveal the quantum correlation of the pair.Some properties of the measure function are proved.

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