Z. Hussain

Evidence for ubiquitous strong electron-phonon coupling in high-temperature superconductors.

Coupling between electrons and phonons (lattice vibrations) drives the formation of the electron pairs responsible for conventional superconductivity. The lack of direct evidence for electron–phonon coupling in the electron dynamics of the high-transition-temperature superconductors has driven an intensive search for an alternative mechanism. A coupling of an electron with a phonon would result in an abrupt change of its velocity and scattering rate near the phonon energy. Here we use angle-resolved photoemission spectroscopy to probe electron dynamics—velocityxa0and scattering rate—for three different families of copper oxide superconductors. We see in all of these materials an abrupt change of electron velocity at 50–80u2009meV, which we cannot explain by any known process other than to invoke coupling with the phonons associated with the movement of the oxygen atoms. This suggests that electron–phonon coupling strongly influences the electron dynamics in the high-temperature superconductors, and must therefore be included in any microscopic theory of superconductivity.

Monochromatic electron photoemission from diamondoid monolayers.

We found monochromatic electron photoemission from large-area self-assembled monolayers of a functionalized diamondoid, [121]tetramantane-6-thiol. Photoelectron spectra of the diamondoid monolayers exhibited a peak at the low–kinetic energy threshold; up to 68% of all emitted electrons were emitted within this single energy peak. The intensity of the emission peak is indicative of diamondoids being negative electron affinity materials. With an energy distribution width of less than 0.5 electron volts, this source of monochromatic electrons may find application in technologies such as electron microscopy, electron beam lithography, and field-emission flat-panel displays.

Metallic behavior of lightly doped La2-xSrxCuO4 with a Fermi surface forming an arc.

Lightly-doped La

Nodal quasiparticle in pseudogapped colossal magnetoresistive manganites

_{2-x}

Dichotomy between nodal and antinodal quasiparticles in underdoped (La2-xSrx)CuO4 superconductors.

Sr

Dual nature of the electronic structure of (La2-x-yNdySrx)CuO4 and La1.85Sr0.15CuO4

_x

Fermi surface reconstruction in the CDW state of CeTe3 observed by photoemission

CuO

Direct extraction of the Eliashberg function for electron-phonon coupling: A case study of Be(1010)

_4

Anomalous fermi-surface dependent pairing in a self-doped high-Tc superconductor

in the so-called insulating spin-glass/diagonal-stripe phase has been studied by angle-resolved photoemission spectroscopy. A quasi-particle (QP) peak crossing the Fermi level has been observed in the node direction of the d-wave superconducting gap, forming an arc of Fermi surface consistent with the recently observed metallic transport behavior at high temperatures of lightly-doped materials. The spectral weight of the nodal QP smoothly increases with hole doping, corresponding to the

Orientation-dependent C60 electronic structures revealed by photoemission

n sim x