Effects of Ca doping and O deficiency on the charge distribution in the vicinity of a 45°  grain boundary in YBa2Cu3O7
KAUST, PSE Division - Thuwal 23955-6900, Kingdom of Saudi Arabia
2 Institut für Physik, Universität Augsburg - 86135 Augsburg, Germany, EU
Accepted: 4 January 2012
The charge redistribution at grain boundaries is critical for the applicability of high-Tc superconductors in electronic devices, because it determines the transport across the material. We investigate the charge transfer and the alterations of the electronic states due to local doping of a normal-state 45°-tilted  grain boundary in YBa2Cu3O7 by means of first-principles calculations. Considering Ca doping and O deficiency as prototypical modifications we demonstrate that the redistribution of the charge carriers in the CuO2 planes displays a very complex spatial pattern, which deviates even qualitatively from the naive expectation.
PACS: 73.20.-r – Electron states at surfaces and interfaces / 74.72.-h – Cuprate superconductors / 74.25.Jb – Electronic structure (photoemission, etc.)
© EPLA, 2012