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Entanglement Observables and Witnesses for Interacting Quantum Spin Systems

L. -A. Wu·S. Bandyopadhyay·M. S. Sarandy·D. A. Lidar
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Abstract

We discuss the detection of entanglement in interacting quantum spin systems. First, thermodynamic Hamiltonian-based witnesses are computed for a general class of one-dimensional spin-1/2 models. Second, we introduce optimal bipartite entanglement observables. We show that a bipartite entanglement measure can generally be associated to a set of independent two-body spin observables whose expectation values can be used to witness entanglement. The number of necessary observables is ruled by the symmetries of the model. Illustrative examples are presented.

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L. -A. Wu, S. Bandyopadhyay, M. S. Sarandy, D. A. Lidar. 2005-09-19. Entanglement Observables and Witnesses for Interacting Quantum Spin Systems. https://doi.org/10.1103/physreva.72.032309

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