Van Hove singularity and d-wave pairing in disordered superconductors
G Litak, AM Martin, BL Gyorffy, JF Annett, KI Wysokinski
Physica C Superconductivity | ELSEVIER SCIENCE BV | Published : 1998
We apply the coherent potential approximation (CPA) to a simple model for disordered superconductors with d-wave pairing and demonstrate that whilst the effectiveness of an electronic Van Hove singularity to enhance the transition temperature Tc is reduced by disorder it is not eliminated. In fact we give a qualitative account of changes in the Tc vs. doping curve with increasing disorder and compare our results with experiments on the Y0-8Ca0.2Ba2(Cu1-yZn y)3O7-δ8 alloys. © 1998 Published by Elsevier Science B.V. All rights reserved.