Eur. Phys. J. B 18, 377-384 (2000)
https://doi.org/10.1007/s100510070022

Electronic spectrum in a microscopical model for the Zn-doped CuO₂ plane

¹ Joint Institute for Nuclear Research, 141980 Dubna, Russia
² Faculty of Natural Sciences and Mathematics, University of Montenegro, PO Box 211, 81001 Podgorica, Yugoslavia
³ Institute for Theoretical Physics, University of Technology Dresden, 01062 Dresden, Germany
⁴ Institute for Solid State and Materials Research, PO Box 270016, 01171 Dresden, Germany

Corresponding author: ^a I.Chaplygin@ifw-dresden.de

Received: 24 May 2000
Revised: 1 August 2000
Published online: 15 December 2000

Abstract

We consider a microscopical model for the Zn-doped CuO₂ plane with Zn impurities being described as vacancies for the d-states on Cu sites. A reduction of the original p-d model to an effective one-band model results in the t-J model with vacancies for the spin 1/2 d-states at the Zn-sites. By employing the T-matrix formalism for the Green functions in terms of the Hubbard operators the density of electronic states (DOS) is calculated. Symmetry analysis of the perturbation matrix shows that in the system with d-type electronic wave functions additional DOS of d-, p- and s-types appear due to the perturbation of local energy levels and the interaction between nearest neighbors around the vacancy. The local and resonant state formation caused by Zn impurities is analyzed.