title: Suppression of Superfluid Density and the Pseudogap State in the Cuprates by Impurities.
abstract: We use scanning tunneling microscopy (STM) to study magnetic Fe impurities intentionally doped into the high-temperature superconductor Bi_{2}Sr_{2}CaCu_{2}O_{8+δ}. Our spectroscopic measurements reveal that Fe impurities introduce low-lying resonances in the density of states at Ω_{1}≈4  meV and Ω_{2}≈15  meV, allowing us to determine that, despite having a large magnetic moment, potential scattering of quasiparticles by Fe impurities dominates magnetic scattering. In addition, using high-resolution spatial characterizations of the local density of states near and away from Fe impurities, we detail the spatial extent of impurity-affected regions as well as provide a local view of impurity-induced effects on the superconducting and pseudogap states. Our studies of Fe impurities, when combined with a reinterpretation of earlier STM work in the context of a two-gap scenario, allow us to present a unified view of the atomic-scale effects of elemental impurities on the pseudogap and superconducting states in hole-doped cuprates; this may help resolve a previously assumed dichotomy between the effects of magnetic and nonmagnetic impurities in these materials.
authors.affiliation: Department of Physics, Clark University, Worcester, Massachusetts 01610, USA.
authors.forename: Unurbat
authors.initials: U
authors.lastname: Erdenemunkh
authors.affiliation: Department of Physics, Clark University, Worcester, Massachusetts 01610, USA.
authors.forename: Brian
authors.initials: B
authors.lastname: Koopman
authors.affiliation: Department of Physics, Clark University, Worcester, Massachusetts 01610, USA.
authors.forename: Ling
authors.initials: L
authors.lastname: Fu
authors.affiliation: Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
authors.forename: Kamalesh
authors.initials: K
authors.lastname: Chatterjee
authors.affiliation: Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
authors.forename: W D
authors.initials: WD
authors.lastname: Wise
authors.affiliation: Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA.
authors.forename: G D
authors.initials: GD
authors.lastname: Gu
authors.affiliation: Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.|Department of Physics, Pennsylvania State University, State College, Pennsylvania 16802, USA.
authors.forename: E W
authors.initials: EW
authors.lastname: Hudson
authors.affiliation: Department of Physics, Clark University, Worcester, Massachusetts 01610, USA.|Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
authors.forename: Michael C
authors.initials: MC
authors.lastname: Boyer