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Mixture of multiple copies of maximally entangled states is quasi-pure

Dong Yang·Yi-Xin Chen
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Abstract

Employing the general BXOR operation and local state discrimination, the mixed state of the form ρ^{(k)}_{d}=\frac{1}{d^{2}}\sum_{m,n=0}^{d-1}(|ϕ_{mn}><ϕ_{mn}|)^{\otim es k} is proved to be quasi-pure, where $\{|ϕ_{mn}>\}$ is the canonical set of mutually orthogonal maximally entangled states in $d\times d$. Therefore irreversibility does not occur in the process of distillation for this family of states. Also, the distillable entanglement is calculated explicitly.

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Dong Yang, Yi-Xin Chen. 2003-07-25. Mixture of multiple copies of maximally entangled states is quasi-pure. https://doi.org/10.1103/physreva.69.024302

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