11 Result(s)
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Article
Evidence of d-wave pairing in the thermal conductivity of YBa2Cu3O7−d and Bi2Sr2CaCu2O8 single crystals
The electronic contribution to the thermal conductivity of a d x 2−y 2-wave superconductor is calculated within a variational method. By considering the scattering ...
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Article
Field percolation and high current density in 80/20 DyBa2Cu3O7 − x/Dy2BaCuO5 bulk magnetically textured composite ceramics
We measured the AC susceptibility of magnetically textured (123) 80%/211(20%) DyBaCuO composite in a special set-up in order to enhance the intergrain contribution. The synthesis process led to very clean “wea...
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Article
Influence of a non-uniform current density profile on quasiparticle excitations and thermally activated flux creep in YBa2Cu3O7−σ
The transport current density, flowing radially from the center of a superconducting disk to its perimeter, in a so-called Corbino geometry, results in a double action on the vortex motion when the applied mag...
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Article
Non-isovalent alkali metal “substitution” in YBa2Cu3O7−y granular ceramics
The aim of this paper is to study the influence of non-isovalent “do**” in YBa2Cu3O7−y in particular on its synthesis conditions and on the resistive properties both with and without a magnetic field. We conce...
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Article
Magnetotransport study of in situ magnetic field textured Dy1Ba2Cu3O7−δ superconductors
The electrical resistivity, thermoelectric power and the Nernst effect have been studied as a function of temperature and magnetic field for a typical superconductor DyBa2Cu3O7−δ magnetically textured in situ at ...
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Article
Systems of reduced electron concentration and dimensionality
Semi-conductors, semi-metals and high critical temperature superconductors are systems with a reduced number of carriers and present effects which are sometimes related to a reduced dimensionality. We consider...
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Article
Theory of thermoelectric power of model semimetals and semiconductors
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Article
Superconductivity fluctuations in Bi(Pb) based granular ceramics superconductors: evidence for fractal behavior
We report precise measurements of the electrical resistivity in three different Bi(Pb) based granular ceramics superconductors. We show that a single critical exponent (5/6) describes the superconductivity flu...
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Article
High temperature crossover in paraconductivity of granular Y1Ba2Cu3O7-y
We have examined the deviation from linearity of the temperature dependence of the electrical resistivity of a YBaCuO ceramics. We have observed at high temprature a crossover behavior toward a logarithmic tem...
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Article
Theory of the thermoelectric power of model semimetals and semiconductors
We briefly discuss available theories as well as hypotheses behind numerical work for the thermoelectric power (TEP). In particular we emphasize shortcomings for comparing usual theoretical and numerical resul...
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Article
Dimensionality crossover regimes due to microcrystalline anisotropy in the resistivity of granular Y1Ba2Cu3O7−y in weak magnetic fields at low temperature
Precise measurements of the electrical resitivity of Y1Ba2Cu3O7−y have been taken in the temperature range between the “percolation transition” temperatureT R and the “superco...
