English

Andreev states near short-ranged pairing potential impurities

Superconductivity 2009-11-11 v1 Strongly Correlated Electrons

Abstract

We study Andreev states near atomic scale modulations in the pairing potential in both ss- and d-wave superconductors with short coherence lengths. For a moderate reduction of the local gap, the states exist only close to the gap edge. If one allows for local sign changes of the order parameter, however, resonances can occur at energies close to the Fermi level. The local density of states (LDOS) around such pairing potential defects strongly resembles the patterns observed by tunneling measurements around Zn impurities in Bi2_2Sr2_2CaCu2_2O8+x_{8+x} (BSCCO). We discuss how this phase impurity model of the Zn LDOS pattern can be distinguished from other proposals experimentally.

Keywords

Cite

@article{arxiv.cond-mat/0507661,
  title  = {Andreev states near short-ranged pairing potential impurities},
  author = {Brian M. Andersen and Ashot Melikyan and Tamara S. Nunner and P. J. Hirschfeld},
  journal= {arXiv preprint arXiv:cond-mat/0507661},
  year   = {2009}
}

Comments

4 pages, 4 figures