Suppression of shock excitation and nonlinear process of acoustic domains in CdS caused by a twohyphen;step pulse application

摘要

The acoustic domains in CdS caused by the twohyphen;step pulse are studied withEfan ultrasonic injection method and Brillouin scattering measurement. When the firsthyphen;step fieldEfis smaller than the synchronous fieldEai.e.,Efquest;Eathinsp;, the factormoffm(thinsp;f; frequency) of the lattice attenuation (agr;l) increases with increasingEfand we finally obtainedm= 2 atEf=Ea. This means that the deviation fromf2.0is caused not only by the nonlinear process but also by the shock excitation. On the other hand, whenEfgsim;Ea, the amplitude of the current waveform decreased drastically and the maximum intensity of the frequency spectra becomes weak and itrsquo;s frequency becomes higher. This means that the nonlinear process is suppressed.