Paraconductivity and Excess Hall Effect in Epitaxial YBa2Cu3O7 Films Induced by Superconducting Fluctuations

Autor(en)

W. Lang, G. Heine, P. Schwab, X.Z. Wang, D. Bauerle

Abstrakt

Measurements of the temperature dependence of the electrical resistivity and the Hall effect in epitaxial films of YBa2Cu3O7 are reported. The resistivity is close to linear in T and the cotangent of the Hall angle proportional to JO at temperatures sufficiently above T(c). Deviations from this behavior near T(c) are attributed to thermodynamic fluctuations and are analyzed in terms of theories for direct (Aslamazov-Larkin) and indirect (Maki-Thompson) fluctuation contributions in a layered superconductor. We obtain an unequivocal fit to both paraconductivity and excess-Hall-effect data with a consistent set of three parameters, i.e., the c-axis coherence length xi(c) (0) = 1.5 angstrom, the phase-relaxation time tau(phi) = 8.6 X 10(-14) s at 100 K, and the electron-hole asymmetry parameter beta = -0.17. We observe a sign change of the excess Hall effect close to T(c), when the Aslamazov-Larkin process becomes dominant.

Organisation(en)

Elektronische Materialeigenschaften

Journal

Physical Review B

Band

49

Seiten

4209-4217

Anzahl der Seiten

9

ISSN

1098-0121

DOI

https://doi.org/10.1103/PhysRevB.49.4209

Publikationsdatum

1994

Peer-reviewed

Ja

ÖFOS 2012

103018 Materialphysik

Schlagwörter

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/b4a6214c-ffed-4452-aedf-c5cdfe2edeb3