Giant oscillations in the magnetoacoustic attenuation of bismuth

Abstract

Measurements of the magnetoacoustic attenuation of bismuth at temperatures of 1.4-1.8°K in transverse magnetic fields up to 17 kG are reported. For shear waves of frequency 8-40 Mc/sec, propagated in the bisectrix direction, with the magnetic field in the binary direction, oscillations in the magnetoacoustic attenuation coefficient as large as 17 db/cm are observed. The oscillations in attenuation coefficient are approximately periodic in the reciprocal of the magnetic field with a period of 6.3×10-5Oe-1, a value corresponding to the smallest cyclotron mass. The data are compared with current theories and are found to be in qualitative agreement. More detailed comparison, however, indicates the need for a more sophisticated theory of the giant oscillations which takes into account the effects of finite electronic mean free path and deviations from parabolicity of the conduction bands. The data presented were obtained using a new and versatile sampling technique which involves the use of a commerical sampling oscilloscope. © 1965 The American Physical Society.