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Entanglement Scaling in the One-Dimensional Hubbard Model at Criticality

Daniel Larsson·Henrik Johannesson
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Abstract

We derive exact expressions for the local entanglement entropy E in the ground state of the one-dimensional Hubbard model at a quantum phase transition driven by a change in magnetic field h or chemical potential u. The leading divergences of dE/dh and dE/du are shown to be directly related to those of the zero-temperature spin and charge susceptibilities. Logarithmic corrections to scaling signal a change in the number of local states accessible to the system as it undergoes the transition.

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Daniel Larsson, Henrik Johannesson. 2006-03-02. Entanglement Scaling in the One-Dimensional Hubbard Model at Criticality. https://doi.org/10.1103/physrevlett.95.196406

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