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arXiv · 1207.7226

An Operational Meaning of Discord in terms of Teleportation Fidelity

Satyabrata Adhikari·Subhashish Banerjee
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Abstract

Quantum discord is a prominent measure of quantum correlations, playing an important role in expanding its horizon beyond entanglement. Here we provide an operational meaning of (geometric) discord, which quantifies the amount of non-classical correlation of an arbitrary quantum system in terms of its minimal distance from the set of classical states, in terms of teleportation fidelity for general two qubit and $d \otimes d$ dimensional isotropic and Werner states. A critical value of the discord is found beyond which the two qubit state must violate the Bell inequality. This is illustrated by an open system model of a dissipative two qubit. For the $d \otimes d$ dimensional states the lower bound of discord is shown to be obtainable from an experimentally measurable witness operator.

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Satyabrata Adhikari, Subhashish Banerjee. 2012-07-31. An Operational Meaning of Discord in terms of Teleportation Fidelity. https://doi.org/10.1103/physreva.86.062313

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