Doping dependence of the electron-doped cuprate superconductors from the antiferromagnetic properties of the Hubbard model

Abstract

Within the Kotliar-Ruckenstein slave-boson approach, we have studied the antiferromagnetic (AF) properties for the $t$-$t^{\prime }$-$t^{\prime \prime }$-$U$ model applied to electron-doped cuprate superconductors. Due to inclusion of spin fluctuations the AF order decreases with doping much faster than obtained in the Hartree-Fock theory. Under an intermediate {\it constant} $U$ the calculated doping evolution of the spectral intensity has satisfactorily reproduced the experimental results, without need of a strongly doping-dependent $U$ as argued earlier. This may reconcile a discrepancy suggested in recent studies on photoemission and optical conductivity.

5 pages, 4 eps figures, minor improvement, references added, to appear in Phys. Rev. B