Journal de Physique I

Sommaire

DOI: 10.1051/jp1:1992162
J. Phys. I France 2 (1992) 517-522

Conductivity coherence peak in YBa ₂Cu ₃O ₇

O. Klein¹, K. Holczer¹, G. Grüner¹ and G.A. Emelchenko²

¹ UCLA, Department of Physics, Los Angeles, CA 90024, U.S.A.
² Academy of Sciences, 142432 Chernogolovka, Moscow, Russia

(Received 20 January 1992, accepted in final form 6 March 1992)

Abstract
We have measured both the surface resistance $R_{\rm s}$ and the surface reactance $X_{\rm s}$ of a YBa ₂Cu ₃O ₇ single crystal at millimeter wave frequencies and have evaluated the conductivity $\sigma_1$ . We observe a narrow coherence peak below $T_{\rm c}$ which indicates s-wave pairing with a rapid opening of the single particle gap.

Conductivity coherence peak in YBa 2Cu 3O 7

Conductivity coherence peak in YBa ₂Cu ₃O ₇