Some Properties of the Spin-Polarized Attractive Hubbard Model

Agnieszka Kujawa; Roman Micnas

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arXiv · 0809.1420

Some Properties of the Spin-Polarized Attractive Hubbard Model

Agnieszka Kujawa·Roman Micnas

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Abstract

The influence of a Zeeman magnetic field on the superconducting characteristics of the attractive Hubbard model was investigated. The ground state and temperature phase diagrams were obtained for a fixed number of particles. Two critical magnetic fields were found for the first order phase transition from the superconducting to the normal state for $n\neq 1$. For some range of parameters a reentrant transition was found and gapless superconductivity was obtained. The significance of the Hartree term was also analyzed.

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Agnieszka Kujawa, Roman Micnas. 2009-02-24. Some Properties of the Spin-Polarized Attractive Hubbard Model. https://arxiv.org/abs/0809.1420

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