Magnetophonon Resonance in n-Type Germanium at Low Temperatures

Abstract

Investigations of hot electron magnetophonon resonance are carried out in n-Ge at low temperatures (10–20 K) by measuring second derivatives of the longitudinal magnetoconductance with magnetic fields applied in the ⟨100⟩, ⟨110⟩ and ⟨111⟩ directions and new series which have not been observed at high temperatures are resolved for the first time. In addition to the intravalley magnetophonon resonance due to the Γ-point LO phonons (439 K) intervalley magnetophonon resonance due to the X₁-point (LA, LO) phonons (347 K) and X₃-point TA phonons (116 K) are observed in the three directions. In the case of J//B//⟨111⟩ impurity magnetophonon series due to the emission of the LO phonons and X₄-point TO phonons (280 K) accompanied by capture of a 1s ground state of donor were detected.