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arXiv · 0903.4553

Extraction of Pure Entangled States from Many Body Systems by Distant Local Projections

J. Molina-Vilaplana·H. Wichterich·V. E. Korepin·S. Bose
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Abstract

We study the feasibility of extracting a pure entangled state of non-complementary, and potentially well separated, regions of a quantum many-body system. It is shown that this can indeed be accomplished in non-equilibrium scenarios as well as the ground state of the considered spin chain models when one locally measures observables such as magnetization in separated blocks of spins. A general procedure is presented, which can search for the optimal way to extract a pure entangled state through local projections. Our results indicate a connection of the projective extraction of entanglement to good quantum numbers of the underlying Hamiltonian.

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J. Molina-Vilaplana, H. Wichterich, V. E. Korepin, S. Bose. 2009-03-26. Extraction of Pure Entangled States from Many Body Systems by Distant Local Projections. https://doi.org/10.1103/physreva.79.062310

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