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Spectral function and quasiparticle weight in the generalized t-J model

F. Lema·A. A. Aligia
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Abstract

We extend to the spectral function an approach which allowed us to calculate the quasiparticle weight for destruction of a real electron Z_c sigma (k) (in contrast to that of creation of a spinless holon Z_h(k) in a generalized $t-J$ model, using the self-consistent Born approximation (SCBA). We compare our results with those obtained using the alternative approach of Sushkov et al., which also uses the SCBA. The results for Z_c sigma (k) are also compared with results obtained using the string picture and with exact diagonalizations of a 32-site square cluster. While on a qualitative level, all results look similar, our SCBA approach seems to compare better with the ED one. The effect of hopping beyond nearest neighbors, and that of the three-site term are discussed.

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F. Lema, A. A. Aligia. 1998-09-28. Spectral function and quasiparticle weight in the generalized t-J model. https://doi.org/10.1016/s0921-4534(98)00501-2

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