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Electronic impurity-state at non-magnetic atom. Electronic impurity-state at magnetic atom. Zn On-site LDOS spectrum: W 0 =-1.5 meV. Magnetic Ni Atom. Non-magnetic Zn Atom. Bi 2 Sr 2 Ca(Cu 1-x Zn x ) 2 O 8+d : x  0. 3 % LDOS map at –1.5mV.

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Electronic impurity-state at non-magnetic atom

Electronic impurity-state at magnetic atom

Zn On-site LDOS spectrum: W0=-1.5 meV

Magnetic Ni Atom

Non-magnetic Zn Atom

Bi2Sr2Ca(Cu1-xZnx)2O8+d: x  0.3%

LDOS map at –1.5mV

Ni On-site LDOS spectrum: W1~9 meV, W2~19 meV

  • M.I. Salkola, A.V. Balatsky, J.R. Schrieffer, Phys. Rev. B55, 12648 (1997).

  • M.E. Flatté and J.M. Byers, Sol. State. Phys.52, 137 (1999).

    • Balatsky, A.V., Salkola M.I., & Rosengren, A., Phys. Rev. B51, 15547 (1995).

    • Salkola, M.I., Balatsky, A.V., & Scalapino, D.J. Phys. Rev. Lett. 77, 1841 (1996).

    Ni impurity-state location and orientation to dx2-y2 gap nodes

    +9 mV

    LDOS Image at W

    |Y|2 for impurity-state

    Spin-up

    Zn Atom

    Closed d-shell

    U>>0

    S=0

    On-site

    LDOS Image |Y|2 at both states

    • V(r)=Ud(r)+JS.s

    • |U|>|W| & U<0

    32 Å

    32 Å

    Ni Atom

    d8

    U<0

    S=1

    Spin-down

    Hole

    10,000 Bi atoms

    ~20 Zn atoms

    CuO2 Plane

    CuO2 Plane

    91118a00 +9mV

    !

    Run 147: #26

    91126K00-19 Typical Spectrum (3a above Ni Center)

    91127E00-20 Center Spectrum

    91117h14

    0 560 Å

    3.75” sq. at

    1.55”, 2”

    3.75” sq. at

    5.8”, 2”

    0 Å 60 Å

    0 Å 60 Å

    b

    a

    0 Å

    0 Å

    3.8 Å

    3.8 Å

    0 Å 60 Å

    0 Å 60 Å

    • Potential scattering generates intra-gap impurity-state

    • Magnetic interactions lift the spin-degeneracy

    • Two spin-polarized states created at W1 and W2

    • On-site component of both impurity-states is four-fold symmetric,

    • pointing at gap nodes.

    • Potential scattering should generate intra-gap state: Impurity-state is four-fold symmetric

    • Oriented with gap nodes.

    Topography (BiO Plane)

    Conductance Map, V = -1 mV

    0 560 Å

    Junction Setpoint: 200 pA @ -200 mV

    Junction Setpoint: 200 pA @ -200 mV

    Nature 403, 746 (2000).

    Nature 403, 746 (2000).

    Nature 411 920 (2001).

    Nature 411 920 (2001).

    Imaging the Effects of Individual Impurity Atoms

    in High-Tc Superconductors

    E.W. Hudson, K. M. Lang, J. E. Hoffman, S. H. Pan, H. Eisaki, S. Uchida & J. C. Seamus Davis

    Bi2Sr2Ca(Cu1-xZnx)2O8+d: x0.3%

    Topo.

    20,000 Bi atoms

    ~20 Zn atoms

    0 560 Å

    0 560 Å

    T = 4.2 K

    200 pA, -200 mV

    Nature 403, 746 (2000).

    Zn impurity-state location and orientation to dx2-y2 gap nodes

    b

    a

    Junction Setpoint: 200 pA @ -200 mV

    Nature 403, 746 (2000).

    Bi2Sr2Ca(Cu1-xNix)2O8+d: x=0.5%

    Topo.

    256 Å

    5000 Bi atoms

    ~30 Ni atoms

    5.5” sq at

    1.5”, 2.75”

    91114I02

    0 Å 256 Å

    T = 4.2 K

    100 pA, -100 mV

    Nature 411 920 (2001).

    Bi2Sr2Ca(Cu1-xNix)2O8+d: x=0.5%

    LDOS map at +10 mV

    256 Å

    2500 Bi atoms

    ~30 Ni atoms

    91119c01 +10mV

    +10 mV

    0 Å 256 Å

    T = 4.2 K

    100 pA, -100 mV

    Nature 411 920 (2001).

    Research Support:


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