Density functional approach to the electronic structure of doped cuprates

Helmut Eschrig

IFW Dresden, P. O. Box 27 00 16, 01171 Dresden, Germany

Results of LSDA+U+CPA total energy and electronic structure calculations for Ca(1-x)KxCuO2, taken as a model substance for hole doped planar cuprates, are presented for hypothetical non-magnetic, spin glass, ferromagnetic and antiferromagnetic spin states are presented. The calculations use the high precision all-electron full-potential local-orbital code (FPLO). Both chemical disorder on the cation site and spin disorder on the copper site are treated within the coherent potential approximation (CPA). Local correlation is treated by a Hubbard U parameter. The results are discussed with respect to magnetic intersite couplings. Spectral functions (band structures) are dicussed with respect to a probable doping dependence of local correlations.