DYNAMICS AND KINETICS OF CARRIER SYSTEM IN PHOTOEXCITED GE AND SI OBSERVED BY OPTICALLY DETECTED CYCLOTRON-RESONANCE

We have observed optically detected cyclotron resonance (ODCR) in Ge and Si. Complicated but outstanding signals have been observed in As-doped Ge. They are explained on the basis of our results obtained earlier. As for Si, kinetics of a system consisting of free carriers, free and bound excitons, bound multiexciton complexes and electron-hole droplets under cyclotron resonance condition is analyzed by means of rate equations, together with "effective temperature" introduced. Besides, the change in photoluminescence spectrum caused by cyclotron resonance is compared with that caused by DC electric field, where a new advantage of ODCR is found.