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arXiv · 1512.05551

Entanglement-fluctuation relation for bipartite pure states

Aura Mae B. Villaruel·Francis N. C. Paraan
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Abstract

We identify subsystem fluctuations (variances) that measure entanglement in an arbitrary bipartite pure state. These fluctuations are of observables that generalize the notion of polarization to an arbitrary N-level subsystem. We express this polarization fluctuation in terms of subsystem purity and other entanglement measures. The derived fluctuation-entanglement relation is evaluated for the ground states of a one-dimensional free fermion gas and the Affleck-Kennedy-Lieb-Tasaki spin chain. Our results provide a framework for experimentally measuring entanglement using Stern-Gerlach-type state selectors.

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Aura Mae B. Villaruel, Francis N. C. Paraan. 2016-08-12. Entanglement-fluctuation relation for bipartite pure states. https://doi.org/10.1103/physreva.94.022323

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