CALCULATION OF DILATIONAL AND UNIAXIAL SHEAR POTENTIALS OF GE BY A STATE-INDEPENDENT MANY-BODY PROJECTION TECHNIQUE

Utilizing state-independent projection operators, we present a new opt ical conductivity formula for cyclotron transition in the system of el ectrons interacting anisotropically with phonons. The line-shape facto r appearing in the conductivity tensor contains the many body effects for electrons phonons. Applying this formula, we determine the two def ormation potentials (dilation potential Xi(d) and uniaxial sheer poten tial Xi(u)) of Ge in the quantum limit. By fitting the present theoret ical values with the experimental data of Murase, Enjouji and Otsuka [ J. Phys. Soc. Jpn. 29 (1970) 1248] and Kobori, Ohyama and Otsuka [J. P hys. Sac. Jpn. 59 (1990) 2141]; me obtain Xi(u) = 17.0 +/- 0.6 eV and Xi(d) = -10.88 +/- 0.47 eV.