Ultrasonic Harmonic Generation in Magnetic Fields

Second-harmonic generation of ultrasound propagating transverse to a dc magnetic field in a piezoelectric semiconductor is treated using a phenomenological approach which is valid when either qR1 or ql1. We find that the magnetic field can change both the magnitude of the harmonic generation and the frequency at which the harmonic generation has its peak value. It is found that at frequencies near or below the frequency of maximum gain the magnitude of the harmonic generation has a maximum as a function of magnetic field. Therefore, the application of a transverse magnetic field can lead to an enhancement of second-harmonic generation in a piezoelectric semiconductor.