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Nonergodicity of entanglement and its complementary behavior to magnetization in infinite spin chain

Aditi Sen De·Ujjwal Sen·Maciej Lewenstein
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Abstract

We consider the problem of the validity of a statistical mechanical description of two-site entanglement in an infinite spin chain described by the XY model Hamiltonian. We show that the two-site entanglement of the state, evolved from the initial equilibrium state, after a change of the magnetic field, does not approach its equilibrium value. This suggests that two-site entanglement, like (single-site) magnetization, is a nonergodic quantity in this model. Moreover we show that these two nonergodic quantities behave in a complementary way.

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Aditi Sen De, Ujjwal Sen, Maciej Lewenstein. 2005-03-17. Nonergodicity of entanglement and its complementary behavior to magnetization in infinite spin chain. https://doi.org/10.1103/physreva.70.060304

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