抄録
Far-infrared magnetoplasma absorption due to electron-hole drops in pure germanium is observed in laser transmission measurements for eleven wavelengths (84 to 513 μm). From the oscillatory behavior in short wavelength absorption, it is concluded that the carrier-pair density in the drop remains constant (2.2×1017 cm−3) up to 20 kOe and increases to 2.7×1017 cm−3 at 50 kOe after first decreasing to 2.0×1017 cm−3 at ∼25 kOe. The relaxation time in the drop is calculated from the linewidth of the peak of 337 μm absorption at ∼38 kOe and it has a temperature dependence of the form 1⁄τ=α+βT2 with α=(2.1±0.1)×1011 s−1 and β=(1.2±0.1)×1010 deg−2s−1. It is strongly suggested that carrier-carrier scattering is the dominant mechanism for the relaxation process in the electron-hole drop.
