Theory of the input power-dependence of the electron heating in n-inversion layers

The average energy loss P of hot electrons due to the interaction with acoustic bulk phonons is calculated and used to determine the electron heating temperature ∆ as a function of the input power eμ E². It is found that P creases proportional to ∆ ² and is independent of the carrier concentration. Consequently the ratio ∆/√ eμ E² turns out to be a constant (0.75 × 10 ^-2 K/(eV/s) ^{1}/{2} for n-Si and 2.04 × 10 ^-2 K/(eV/s) ^{1}/{2} for n-GaAs) in agreement with the experimental data deduced from FIR-emission experiments at T = 4.2 K.