Angle-resolved photoemission data and quasiparticle spectra in antiferromagnetic insulators Sr2CuO2Cl2 and Ca2CuO2Cl2 -: art. no. 235124

We have analyzed the quasiparticle dispersion and angle-resolved photoemission spectroscopy (ARPES)-spectral density for Sr2CuO2Cl2 and Ca2CuO2Cl2 anti ferromagnetic insulators along basic symmetric directions of the Brillouin zone (BZ) in the framework of a generalized tight binding method (GTBM) with account for strong electron cot-relations. The quasiparticle dispersion is in a good agreement with ARPES data. At the top of the valence band we found a narrow impuritylike virtual level with the spectral weight proportional to the concentration of spin fluctuations. A pseudogap between the virtual level and the top of the valence band has dispersion similar to "remnant Fermi surface" in Ca2CuO2Cl2 and to a pseudogap in the underdoped Bi2Sr2CaCu2O8+d(Dy) (Bi2212) samples. A calculated parity of the polarized ARPES spectra in Gamma ,M,X points in the AFM phase is even with regard to relative magnitudes of the partial contributions from different orbitals to the total ARPES-spectral density. Possible conditions of an observation for the different partial contributions in the polarized ARPES experiments are determined also.