Study of superconducting fluctuations in the high-temperature superconductor YBa2Cu3O7 by magnetotransport measurements

Autor(en)

W. Lang

Abstrakt

The contributions of thermodynamic fluctuations of the superconducting order parameter to the normal-state magneto-conductivity tenser are investigated. Complementary measurements of the electrical resistivity, the Hall effect and the magnetoresistance at temperatures above T-c in thin films of the high-T-c superconductor YBa2Cu3O7 reveal the coherence lengths in the ab-plane, xi(ab)(0) = 1.4 nm, and parallel to the c-axis, xi(c)(0)= 0.15 nm, respectively. The indirect (Maki-Thompson) fluctuation contribution can be detected in the excess Hall effect, but exhibits a different temperature dependence than predicted for s-wave pairing symmetry. It is smaller at higher temperatures than previously estimated from magnetoresistance measurements when the normal state magnetoresistance is correctly included. The results indicate an unconventional pairing state in the cuprate superconductors.

Organisation(en)

Elektronische Materialeigenschaften

Journal

Synthetic Metals

Band

71

Seiten

1555-1558

Anzahl der Seiten

4

ISSN

0379-6779

DOI

https://doi.org/10.1016/0379-6779(94)02949-Y

Publikationsdatum

1995

Peer-reviewed

Ja

ÖFOS 2012

103018 Materialphysik

Schlagwörter

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/7d124ea8-98b6-48d3-8bc0-1d8e56e79352