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arXiv · 0906.2370

Entanglement Properties and Phase Diagram of the Two-Orbital Atomic Hubbard Model

A. Avella·F. Mancini·G. Scelza·S. Chaturvedi
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Abstract

We study the two-orbital Hubbard model in the limit of vanishing kinetic energy. The phase diagram in the $V-J$ plane, with $V$ and $J$ denoting the interorbital hybridization and exchange coupling respectively, at half filling is obtained. A singlet(dimer)-triplet transition is found for a critical value of the ratio $V/J.$ The entropy of formation, both in the mode and in the particle picture, presents a jump as the same critical line in conformity with the suggested relation between criticality and entanglement.

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A. Avella, F. Mancini, G. Scelza, S. Chaturvedi. 2009-06-12. Entanglement Properties and Phase Diagram of the Two-Orbital Atomic Hubbard Model. https://doi.org/10.12693/aphyspola.113.417

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