Magnetophonon Resonance in n-Type Germanium

Abstract

Magnetophonon resonance experiments of transverse magnetoresistance are performed in n-Ge at T =100∼250 K. Magnetophonon oscillations due to both intravalley and intervalley scattering processes are observed. The band edge masses are determined to be m t =0.0823 m 0 and m 1 =1.59 m 0 at T =120 K. The temperature dependence of m t is found to be very weak in the temperature range 100 to 250 K and interpreted by the k · p theory. Fourier transform of the present data reveals a fundamental field 36 T in the case of B //<100>, which is ascribed to the intervalley magnetophonon resonance due to the degenerate LA and LO phonons at the X 1 point (349 K). Deformation potential ratio of the intervalley to intravalley phonon scattering is determined for the first time to be 0.28±0.07, which yields (5.71±1.8)×10 8 eV/cm for the deformation potential of the intravalley LO phonon scattering.