Theory of Cyclotron Resonance Absorption in Many-Valley Semiconductors

A general theory of cyclotron absorption, appropriate for energy-dependent scattering processes, is developed for electron diamagnetic resonance in germanium and silicon. An examination of the absorption arising from intravalley lattice scattering for nondegenerate electrons in germanium based on the restriction of an isotropic, energy-independent mean free path is made over temperatures ranging from liquid nitrogen to liquid helium for the resonance associated with the directional combination of magnetic and electric fields H [001], $\mathrm{E}\left[1\mathrm{}\overline{1}0\right]$. Comparison with the findings associated with the assumption of a constant mean free time reveals that precise absolute power absorption measurements would be required to distinguish between these two mechanisms.