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

M. BEJAS; A. GRECO; A. FOUSSATS

PHYSICAL REVIEW B - CONDENSED MATTER AND MATERIALS PHYSICS

Año: 2006 vol. 73 p. 2451041 - 2451049

0163-1829

 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 occurs. Fermi liquid behavior with scattering rate sim omega² and a finite quasiparticle weight Z was obtained. Z decreases with decreasing doping taking low values for lowdoping. Results are compared with others obtained by analytical and numerical methods like the slave-boson and Lanczos diagonalization approaches, finding agreement. We discuss our results in the light of recent angle-resolved photoemission spectroscopy experiments in cuprates.