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Measuring the entanglement of coupled spins by multiphoton interference

Michael N. Leuenberger·Michael E. Flatte·D. D. Awschalom
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Abstract

We propose an experimental method to measure the entanglement of coupled spins, each in a separate quantum dot, by means of multiphoton interference patterns generated through the scattering of two laser beams off the quantum dots. We calculate the N-photon quantum correlations measured by N detectors on an image plane. Using two perpendicular laser beams, either many correlation measurements on a time ensemble or a single correlation measurement on a spatial ensemble of the many-qubit state is sufficient to retrieve all the possible amplitudes of a many-qubit state.

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Michael N. Leuenberger, Michael E. Flatte, D. D. Awschalom. 2003-09-25. Measuring the entanglement of coupled spins by multiphoton interference. https://arxiv.org/abs/cond-mat/0307657

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