Heating of electron subsystem by the Dember field in ambipolar diffusion in germanium
Gantmakher V.F., Zverev V.N.
When the distribution function of the photoelectrons near the bottom of the lower Landau subband is distorted as a result of heating of the cold electrons by the Dember field, negative conductivity arises in the electron subsystem [V. F. Elesin, Zh. Eksp. Teor. Fiz. 28, 410 (1969)]. It is responsible for the inversion of the magnetic-impurity oscillations of the photomagnetic effect in germanium.