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Fermionic concurrence in the extended Hubbard dimer

Shu-Sa Deng·Shi-Jian Gu·Hai-Qing Lin
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Abstract

In this paper, we introduce and study the fermionic concurrence in a two-site extended Hubbard model. Its behaviors both at the ground state and finite temperatures as function of Coulomb interaction $U$ (on-site) and $V$ (nearest-neighbor) are obtained analytically and numerically. We also investigate the change of the concurrence under a nonuniform field, including local potential and magnetic field, and find that the concurrence can be modulated by these fields.

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Shu-Sa Deng, Shi-Jian Gu, Hai-Qing Lin. 2004-06-12. Fermionic concurrence in the extended Hubbard dimer. https://doi.org/10.1088/0256-307x%2F22%2F4%2F007

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