Effects of Magnetic Field Dependence of Deformation Potentials upon Line Shapes of the Giant Quantum Attenuation of Sound Waves in Bismuth

Abstract

The magnetic field dependence of line shapes of the giant quantum attenuation of longitudinal sound waves in bismuth has been investigated in rather weak magnetic fields but in a low Landau quantum number region. It is shown that when the energy interval between an electron Landau level and a hole level located in the neighborhood of the Fermi level decreases, the attenuation peak on the lower field side of the twin peaks is greatly enhanced in height and sharpened in width, but the temperature dependence of the attenuation coefficient of the lower field peak is almost normal. This apparently anomalous angular dependence of the line shape can be well explained by taking account of peculiar field dependence of the deformation potentials which was overlooked in existing theories of the giant quantum attenuation of sound waves in semimetals.