Density of states in d-wave superconductors disordered by extended   impurities
  The low-energy quasiparticle states of a disordered d-wave superconductor are investigated theoretically. A class of such states, formed via tunneling between the Andreev bound states that are localized around extended impurities (and result from scattering between pair-potential lobes that differ in sign) is identified. Its (divergent) contribution to the total density of states is determined by taking advantage of connections with certain one-dimensional random tight-binding models. The states under discussion should be distinguished from those associated with nodes in the pair potential. 
Inanc Adagideli (1), Daniel E. Sheehy (2), Paul M. Goldbart (3) ((1)   Universiteit Leiden, (2) University of British Columb...