DECAY OF ACOUSTOELECTRIC DOMAIN AND MICROWAVE EMISSION IN N-INSB

The relation between the motion of the acoustoelectric domain and microwave emission in acoustoelectrically oscillating n -InSb was investigated and it was found that the discontinuity at the boundary of anode plays an important role in the microwave emission. The decay of the domain and microwave emission was studied by using a double pulse technique; the built-up domain continued to exist about 1 µsec after switching off the first pulse, but the microwave emission faded out instantaneously. If the second pulse is applied during the decay of the acoustic domain, the microwave emission can be generated again. The square root of the emitted microwave power was proportional to the drift velocity of electrons. These results show that the drift motion of electrons is essential for the microwave emission from n -InSb. In some cases reflected acoustic domain from the anode was observed. Finally the decay of the acoustoelectric domain is explained by considering the contributions from both the three-phonon process between amplified and thermal phonons and the boundary scattering. © 1969, THE PHYSICAL SOCIETY OF JAPAN. All rights reserved.