Measurements were made of electromagnetic generation of ultrasonic shear and longitudinal waves at liquid-helium temperatures in several single crystals of bismuth for each of the three principal crystallographic axes. Measurements were made over the frequency range 5-50 MHz. In addition to giant quantum oscillations (GQO) in the generation efficiency, which were observed in all cases, detailed studies of a pronounced low-field (30-300 G) peak in the generation efficiency are reported. This peak is seen both for shear- and longitudinal-wave generation and is found to depend strongly on a number of parameters, including temperature, rf field strength, frequency, and crystallographic orientation. The frequency dependence of the shear-wave measurements is compared with the recent helicon-phonon interaction theory of Quinn.
No takes yet. Share an insight, caveat, or question.
Hsu et al. (1972) studied this question.
Synapse has enriched 4 closely related papers on similar clinical questions. Consider them for comparative context: