Detailed calculation of energy relaxation time of hot electrons in InSb

The electron temperature T0 and the energy relaxation time τε in n-InSb at 78 K have been quantitatively determined from the microwave complex conductivity measured in the presence of a dc heating field. The well-known assumptions such as ωτm≪1 and (T0−TL)/τε(dτε/dT0) ≪1 are not included in the present calculation, where ω is the angular frequency of microwave field, τm is the momentum relaxation time, and TL is the lattice temperature. The electron temperature increases monotonously as the field increases and reaches about 140 K at 150 V/cm. The energy relaxation time is found to be (1.3–2) ×10−12 sec and to be almost constant for field values above 50 V/cm. The quantity ωτε is large enough to cause strong relaxation effects.