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Spin and Charge Excitations in the Two-Dimensional t-J Model: Comparison with Fermi and Bose Systems

W. O. Putikka·M. U. Luchini·R. R. P. Singh
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Abstract

Using high temperature series we calculate temperature derivatives of the spin-spin and density-density correlation functions to investigate the low energy spin and charge excitations of the two-dimensional t-J model. We find that the temperature derivatives indicate different momentum dependences for the low energy spin and charge excitations. By comparing short distance density-density correlation functions with those of spinless fermions and hard core bosons, we find that the t-J model results are intermediate between the two cases, being closer to those of hard core bosons. The implications of these results for superconductivity are discussed.

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W. O. Putikka, M. U. Luchini, R. R. P. Singh. 1999-12-14. Spin and Charge Excitations in the Two-Dimensional t-J Model: Comparison with Fermi and Bose Systems. https://arxiv.org/abs/cond-mat/9912269

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