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Single-Site Entanglement of Fermions at a Quantum Phase Transition

Daniel Larsson·Henrik Johannesson
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Abstract

We show that the single-site entanglement of a generic spin-1/2 fermionic lattice system can be used as a reliable marker of a finite-order quantum phase transition, given certain provisos. We discuss the information contained in the single-site entanglement measure, and provide illustrations from the Mott-Hubbard metal-insulator transitions of the one-dimensional Hubbard model, and the Hubbard model with long-range hopping.

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Daniel Larsson, Henrik Johannesson. 2006-05-19. Single-Site Entanglement of Fermions at a Quantum Phase Transition. https://doi.org/10.1103/physreva.73.042320

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