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Connecting the geometric measure of entanglement and entanglement witnesses

Tzu-Chieh Wei·Paul M. Goldbart
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Abstract

The geometric measure of entanglement is an approach to quantifying entanglement that is based on the Hilbert-space distance (or, equivalently, angle) between pure states and their best unentangled approximants. An entanglement witness is an operator that reveals entanglement for a given entangled state. A connection is identified between entanglement witnesses and the geometric measure of entanglement. This offers a new interpretation of the geometric measure of entanglement of a state, and renders it experimentally verifiable, doing so most readily for states that are pure.

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Tzu-Chieh Wei, Paul M. Goldbart. 2003-03-13. Connecting the geometric measure of entanglement and entanglement witnesses. https://arxiv.org/abs/quant-ph/0303079

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