An observable measure of entanglement for pure states of multi-qubit systems

Gavin K. Brennen

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An observable measure of entanglement for pure states of multi-qubit systems

Gavin K. Brennen

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Abstract

Recently, Meyer and Wallach [D.A. Meyer and N.R. Wallach (2002), J. of Math. Phys., 43, pp. 4273] proposed a measure of multi-qubit entanglement that is a function on pure states. We find that this function can be interpreted as a physical quantity related to the average purity of the constituent qubits and show how it can be observed in an efficient manner without the need for full quantum state tomography. A possible realization is described for measuring the entanglement of a chain of atomic qubits trapped in a 3D optical lattice.

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Gavin K. Brennen. 2003-11-05. An observable measure of entanglement for pure states of multi-qubit systems. https://arxiv.org/abs/quant-ph/0305094

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