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Sharing Polarization within Quantum Subspaces

M. S. Anwar·J. A. Jones·S. B. Duckett
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Abstract

Given an ensemble of n spins, at least some of which are partially polarized, we investigate the sharing of this polarization within a subspace of k spins. We assume that the sharing results in a pseudopure state, characterized by a single purity parameter which we call the bias. As a concrete example we consider ensembles of spin-1/2 nuclei in liquid-state nuclear magnetic resonance (NMR) systems. The shared bias levels are compared with some current entanglement bounds to determine whether the reduced subspaces can give rise to entangled states.

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M. S. Anwar, J. A. Jones, S. B. Duckett. 2005-12-14. Sharing Polarization within Quantum Subspaces. https://doi.org/10.1103/physreva.73.022322

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