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arXiv · 1510.06531

The $β$-expansion of the $D=1$ fermionic spinless Hubbard model off the half-filling regime

E. V. Corrêa Silva·M. T. Thomaz·O. Rojas
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Abstract

We found that when the spinless model is off the half-filling regime ($μ\neq V$), the Helmholtz free energy (HFE) can be written as two $β$-expansions: one expansion comes from the half-filling configuration and another one that depends on the parameter $x = μ- V$. We show numerically that the chemical potential as a function of temperature satisfies a relation similar to the one derived from the particle-hole symmetry of the fermionic spinless model. We extend the $β$-expansion of the HFE of the one-dimensional fermionic spinless Hubbard model up to order $β^8$.

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E. V. Corrêa Silva, M. T. Thomaz, O. Rojas. 2015-10-22. The $β$-expansion of the $D=1$ fermionic spinless Hubbard model off the half-filling regime. https://doi.org/10.5488/cmp.18.33003

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