NONLINEAR FREQUENCY SHIFT IN ACOUSTOELECTRIC DOMAINS IN GaAs
نویسنده
چکیده
A Bommel-Dransfeld technique is used to analyse the frequency spectrum in GaAs acousto electric domains up to 8 GHz. Parametric frequency conversion is found to be only dominant at the very onset of domain formation. In the strongly nonlinear regime, the amplified noise is mainly concentrated around the shifting frequency of maximum nonlinear gain. The shift of the maximum gain frequency is generally discussed by a theory of nonlinear ultrasound amplification. An evaluation of the measured frequency shifts by this theory leads to the simple relation \x\ ~ 2 y between the domain electric field and the bunching rate.
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