Nonlinear Effects of Sound Waves in High-T_c-Superconductors

Abstract

High-T;superconductors are studied by measuring the ultrasonic attenuation and the relative change of the sound velocity in various applied magnetic fields. High sound amplitudes reveal nonlinear effects of the fluxline lattice. Due to the coupling of the flux lines to the sound waves, the occurring effects show the pinniig behaviour of a high-T,-superconductor. Especially the results for a textured ceramic Bi,,6Pb,,Sr2Ca2Cu30,-superconductor are presented and discussed.