James Storey

Evidence of a Precursor Superconducting Phase at Temperatures as High as 180 K in RBa2Cu3O7-delta (R = Y, Gd, Eu) Superconducting Crystals from Infrared Spectroscopy

A. Dubroka, M. Rössle, K. W. Kim, V. K. Malik, D. Munzar, D. N. Basov, A. Schafgans, S. J. Moon, C. T. Lin, D. Haug, V. Hinkov, B. Keimer, Th. Wolf, J. G. Storey, J. L. Tallon, and C. Bernhard ∗ University of Fribourg, Department of Physics and Fribourg Center for Nanomaterials, Chemin du Musée 3, CH-1700 Fribourg, Switzerland Department of Condensed Matter Physics, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic Department of Physics, University of California, San Diego, La Jolla, California 92093, USA Max-Planck-Institut für Festkörperforschung, Heisenbergstrasse 1, D-70569 Stuttgart, Germany Karlsruhe Institute of Technology, Institut für Festkörperphysik, D-76021 Karlsruhe, Germany MacDiarmid Institute, Industrial Research Ltd., P.O. Box 31310, Lower Hutt, New Zealand (Dated: September 16, 2010)

Isotope effect in the superfluid density of high-temperature superconducting cuprates : Stripes, pseudogap, and impurities

Underdoped cuprates exhibit a normal-state pseudogap, and their spins and doped carriers tend to spatially separate into 1D or 2D stripes. Some view these as central to superconductivity and others as peripheral and merely competing. Using La(2-x)Sr(x)Cu(1-y)Zn(y)O4 we show that an oxygen isotope effect in Tc and in the superfluid density can be used to distinguish between the roles of stripes and pseudogap and also to detect the presence of impurity scattering. We conclude that stripes and pseudogap are distinct, and both compete and coexist with superconductivity.

Coexistence of the superconducting energy gap and pseudogap above and below the transition temperature of cuprate superconductors

We express the superconducting gap,

Saddle-point van Hove singularity and the phase diagram of high- T c cuprates

\Delta(T)

Hall effect and Fermi surface reconstruction via electron pockets in the high-Tc cuprates

, in terms of thermodynamic functions in both

Fermi arcs in cuprate superconductors: Tracking the pseudogap below T c and above T *

s

Electron pockets and pseudogap asymmetry observed in the thermopower of underdoped cuprates

- and d-wave symmetries. Applying to Bi

Thermodynamic properties of Bi2Sr2CaCu2O8 calculated from the electronic dispersion

_2

Pressure dependence of the oxygen isotope effect in the superconductor YBa2Cu4O8

Sr

Fluctuations and critical temperature reduction in cuprate superconductors

_2