摘要We exactly calculate the negativity, a measurement of entanglement, in the two-site extended Hubbard model with external magnetic field. Its behaviour at different temperatures is presented. The negativity reduces with the increasing temperature or with the increasing uniform external magnetic field. It is also found that a non-uniform external magnetic field can be used to modulate or to increase the negativity.
Abstract：We exactly calculate the negativity, a measurement of entanglement, in the two-site extended Hubbard model with external magnetic field. Its behaviour at different temperatures is presented. The negativity reduces with the increasing temperature or with the increasing uniform external magnetic field. It is also found that a non-uniform external magnetic field can be used to modulate or to increase the negativity.
YANG Zhen;NING Wen-Qiang. Negativity in the Extended Hubbard Model under External Magnetic Field[J]. 中国物理快报, 2008, 25(1): 31-34.
YANG Zhen, NING Wen-Qiang. Negativity in the Extended Hubbard Model under External Magnetic Field. Chin. Phys. Lett., 2008, 25(1): 31-34.
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2008, Vol. 25 
