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One-electron self energies and spectral functions for the t-J model in the large-N limit

M. Bejas·A. Greco·A. Foussats
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Abstract

Using a recently developed perturbative approach, which considers Hubbard operators as fundamental excitations, we have performed electronic self-energy and spectral function calculations for the $t-J$ model on the square lattice. We have found that the spectral functions along the Fermi surface are isotropic, even close to the critical doping where the $d$-density wave phase takes place. Fermi liquid behavior with scattering rate $\sim ω^2$ and a finite quasiparticle weight $Z$ was obtained. $Z$ decreases with decreasing doping taking low values for low doping. Results are compared with other ones, analytical and numerical like slave-boson and Lanczos diagonalization finding agreement. We discuss our results in the light of recent $ARPES$ experiments in cuprates.

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M. Bejas, A. Greco, A. Foussats. 2006-04-28. One-electron self energies and spectral functions for the t-J model in the large-N limit. https://doi.org/10.1103/physrevb.73.245104

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