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- Bartkowiak, M., et al.
(författare)
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High-Density Expansion for the Spinless Fermion Model I : First Order in 1/z and Horwitz-Callen Renormalization
- 1988
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Ingår i: International Journal of Modern Physics B. - : World Scientific Publishing. - 0217-9792. ; 2:03-04, s. 483-520
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Tidskriftsartikel (refereegranskat)abstract
- A diagrammatic technique for Hubbard's operators is employed to perform systematically the high-density expansion for the three-dimensional spinless fermion model. The molecular field theory is obtained by the zero-order renormalization of blocks. Summation of the first order diagrams is carried out in both selfconsistent and correctional way. It turns out that the charge ordering parameter, calculated self-consistently, has a jump for a certain medial temperature. We have also shown, that the Horwitz-Callen renormalization leads to the first or second order phase transition, depending on t/W and fails when this ratio is large enough. The phase diagrams of the system for the half-filled band case, derived in both unrenormalized and renormalized first order of high-density expansion are presented.
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