830 research outputs found
On the theory of magnetic field dependence of heat conductivity in dielectric in isotropic model
Phonon polarization in a magnetic field is analyzed in isotropic model. It is
shown, that at presence of spin-phonon interaction phonon possess circular
polari-zation which causes the appearance of heat flux component perpendicular
both to temperature gradient and magnetic field.Comment: 5 pages, 0 figure
Field-Dependent Critical Current in Type-II Superconducting Strips: Combined Effect of Bulk Pinning and Geometrical Edge Barrier
Recent theoretical and experimental research on low-bulk-pinning
superconducting strips has revealed striking dome-like magnetic-field
distributions due to geometrical edge barriers. The observed magnetic-flux
profiles differ strongly from those in strips in which bulk pinning is
dominant. In this paper we theoretically describe the current and field
distributions of a superconducting strip under the combined influence of both a
geometrical edge barrier and bulk pinning at the strip's critical current Ic,
where a longitudinal voltage first appears. We calculate Ic and find its
dependence upon a perpendicular applied magnetic field Ha. The behavior is
governed by a parameter p, defined as the ratio of the bulk-pinning critical
current Ip to the geometrical-barrier critical current Is0. We find that when p
> 2/pi and Ip is field-independent, Ic vs Ha exhibits a plateau for small Ha,
followed by the dependence Ic-Ip ~ 1/Ha in higher magnetic fields.Comment: 4 pages, 2 figures, Fig. 1 revised, submitted to Phys. Rev.
Metallic ground state and glassy transport in single crystalline URhGe: Enhancement of disorder effects in a strongly correlated electron system
We present a detailed study of the electronic transport properties on a
single crystalline specimen of the moderately disordered heavy fermion system
URhGe. For this material, we find glassy electronic transport in a
single crystalline compound. We derive the temperature dependence of the
electrical conductivity and establish metallicity by means of optical
conductivity and Hall effect measurements. The overall behavior of the
electronic transport properties closely resembles that of metallic glasses,
with at low temperatures an additional minor spin disorder contribution. We
argue that this glassy electronic behavior in a crystalline compound reflects
the enhancement of disorder effects as consequence of strong electronic
correlations.Comment: 5 pages, 4 figures, accepted for publication in PR
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