Quantum Effects in Ge and Si. I

Experimental quantum effect spectra have been observed in germanium and silicon at liquid helium temperatures and a frequency of 136 kMc/sec. Detailed spectra are presented for the applied magnetic field in the [100], [111], and [110] directions. Anisotropy data of some of the more intense lines are also presented. Using the theory of Luttinger and Kohn with the assumption of thermal equilibrium, effective masses and line intensities were computed for an applied magnetic field in the [111] direction. By adjusting the parameters of the theory, good agreement was obtained between the theoretical and experimental spectra. The experimentally determined parameters are: These lead to parameters $A=13.2$, $|B|=8.2$, and $|C|=13.3$ for germanium and $A=4.22$, $|B|=1.0$, and $|C|=4.34$ for silicon. (See note added in proof.)