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Series Expansions for Variable Electron Density

Zheng Weihong·C. J. Hamer·J. Oitmaa·R. R. P. Singh
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Abstract

We have developed a series expansion method for calculating the zero-temperature properties of lattice electron models for variable electron density, i.e. for finite doping away from the half-filled case. This is done by introducing particle fluctuation terms in both the unperturbed Hamiltonian and perturbation. The method is demonstrated by application to the 2-chain $t-J$ ladder, where we provide comparison with previous work as well as obtaining a number of new results.

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Zheng Weihong, C. J. Hamer, J. Oitmaa, R. R. P. Singh. 2001-12-20. Series Expansions for Variable Electron Density. https://arxiv.org/abs/cond-mat/0112371

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