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arXiv · 1205.2098

Detecting quantum correlations in separable systems

S. Adhikari·A. S. Majumdar·I. Chakraborty
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Abstract

Quantum correlations in composite and separable quantum systems are characterized by non-vanishing quantum discord. We demonstrate the necessary and sufficient conditions for existence of hermitian witness operators for quantum discord, bypassing the problem of non-convexity of the set of all classical states. We propose an example of a linear witness which can detect quantum correlations in large classes of separable bipartite systems. Decomposition of the witness in terms of a small number of locally measurable operators as shown here, paves the way for experimental detection of quantum correlations beyond entanglement.

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S. Adhikari, A. S. Majumdar, I. Chakraborty. 2012-12-27. Detecting quantum correlations in separable systems. https://arxiv.org/abs/1205.2098

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