title: Interpretation of scanning tunneling quasiparticle interference and impurity states in cuprates.
abstract: We apply a recently developed method combining first principles based Wannier functions with solutions to the Bogoliubov-de Gennes equations to the problem of interpreting STM data in cuprate superconductors. We show that the observed images of Zn on the surface of Bi_{2}Sr_{2}CaCu_{2}O_{8} can only be understood by accounting for the tails of the Cu Wannier functions, which include significant weight on apical O sites in neighboring unit cells. This calculation thus puts earlier crude "filter" theories on a microscopic foundation and solves a long-standing puzzle. We then study quasiparticle interference phenomena induced by out-of-plane weak potential scatterers, and show how patterns long observed in cuprates can be understood in terms of the interference of Wannier functions above the surface. Our results show excellent agreement with experiment and enable a better understanding of novel phenomena in the cuprates via STM imaging.
authors.affiliation: Department of Physics, University of Florida, Gainesville, Florida 32611, USA.|Niels Bohr Institute, University of Copenhagen, DK-2100 Copenhagen, Denmark.
authors.forename: A
authors.initials: A
authors.lastname: Kreisel
authors.affiliation: Department of Physics, University of Florida, Gainesville, Florida 32611, USA.
authors.forename: Peayush
authors.initials: P
authors.lastname: Choubey
authors.affiliation: Center for Nanophase Materials Sciences and Computer Science and Mathematics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA.
authors.forename: T
authors.initials: T
authors.lastname: Berlijn
authors.affiliation: Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA.
authors.forename: W
authors.initials: W
authors.lastname: Ku
authors.affiliation: Niels Bohr Institute, University of Copenhagen, DK-2100 Copenhagen, Denmark.
authors.forename: B M
authors.initials: BM
authors.lastname: Andersen
authors.affiliation: Department of Physics, University of Florida, Gainesville, Florida 32611, USA.
authors.forename: P J
authors.initials: PJ
authors.lastname: Hirschfeld