• Publications
  • Influence
Destruction of the Fermi surface in underdoped high-Tc superconductors
The Fermi surface—the set of points in momentum space describing gapless electronic excitations—is a central concept in the theory of metals. In this context, the normal ‘metallic’ state of the
Disentangling Cooper-pair formation above the transition temperature from the pseudogap state in the cuprates
The pseudogap state in the cuprate superconductors shows signs of electronic pair formation above the superconducting temperature. Is it just a ‘precursor’ state or a separate (and competing) state?
Charge-density-wave origin of cuprate checkerboard visualized by scanning tunnelling microscopy
The checkerboard pattern observed in high-temperature superconductors by scanning tunnelling microscopy is widespread, but what does it mean? And what does it say about the mysterious ’pseudogap’?
Contribution of electronic structure to the large thermoelectric power in layered cobalt oxides
With a strong help of high-resolution photoemission spectroscopy we demonstrate in this paper that the large thermoelectric power observed in the layered cobalt oxides, such as Ca3Co4O9 ,N a 0.6CoO2,
An Oxide Single Crystal with High Thermoelectric Performance in Air
An oxide single-crystalline whisker with high thermoelectric properties at temperatures (T) higher than 600 K in air has been discovered. This whisker is assigned to Ca2Co2O5 phase (abbreviated to
Competition between the pseudogap and superconductivity in the high-Tc copper oxides
It is concluded that the pseudogap competes with the superconductivity by depleting the spectral weight available for pairing, as demonstrated by a study of two spectral weights using angle-resolved photoemission spectroscopy.
Imaging nanoscale Fermi-surface variations in an inhomogeneous superconductor
A variant on Fourier-transform scanning tunnelling spectroscopy enables spatial variations in the Fermi surface of bismuth-based cuprate superconductors to be probed. This technique reveals that
Imaging the two gaps of the high-temperature superconductor Bi 2 Sr 2 CuO 6+ x
The nature and behaviour of electronic states in high-temperature superconductors are the centre of much debate. The pseudogap state, observed above the superconducting transition temperature, Tc, is
Superconducting gap anisotropy and quasiparticle interactions: A doping dependent photoemission study
Comparing photoemission measurements on Bi2212 with penetration depth data, we show that a description of the nodal excitations of the d-wave superconducting state in terms of noninteracting
Evidence for two energy scales in the superconducting state of optimally doped (Bi,Pb)2(Sr,La)2CuO6+delta.
It is speculated that the pseudogap state competes with the superconductivity by diminishing spectral weight in antinodal regions, where thesuperconducting gap is largest.