DYNAMICS OF LIGHT-TRIGGERED GUNN-DOMAIN STRUCTURE - DOMAIN MULTIPLICATION AND CURRENT OSCILLATIONS

In the present work we analyze the evolution of a periodical high-fiel d domain structure, triggered by picosecond or nanosecond light pulses in biased GaAs and InP bulk crystals. We applied a full-hydrodynamic model as well as the Monte Carlo technique to calculate hot carrier tr ansport of nonuniformly heated and spatially modulated carrier plasma. Time-resolved spatial profiles of carrier and internal electric field distribution revealed Gunn-domain splitting and its multiplication to new carrier and field gratings in microwave field. In de field; coher ent drift and fusion of Gunndomain structure lead to oscillations of t he total current which frequency depends on light intensity and modula tion.