EFFECT OF THE PROPAGATION OF ULTRASOUNDS ON MAGNETOACOUSTIC PHENOMENA IN DEGENERATE SEMICONDUCTORS

Abstract
The effect of ultrasounds gropagating at an angle θ relative to the direction of a dc magnetic field [MATH] in degenerate semiconductors such as n-type InSb has been studied by using a quantum treatment which is valid at high frequencies and in strong magnetic fields. The interaction of conduction electrons with ultrasounds is via deformation-potential and piezoelectric couplings. Results show that the absorption coefficient and change in sound velocity oscillate with the dc magnetic field. However, when the direction of the propagation of ultrasounds is not the same as that of the field, both absorption coefficient and change in sound velocity will diminish and become insignificant in the intermediate-magnetic-field region. These results are quite different from those of nondegenerate semiconductors.