Stimulated switch-off and repetitive switching of a bistable optically controlled semiconductor switch

Abstract

The response of CdS:Cu bistable optically controlled semiconductor switches to 10 ns laser pulses had been measured with green (532 nm), red (650 nm) and IR (1064 nm) excitation and pulse mixtures. In addition to light-stimulated conductivity the authors show a new mechanism: the stimulated switch-off with an infrared light pulse. With the present low-doped samples it was possible to realise turn-on times as fast as 15 ns (10-90%) and turn-off times shorter than 250 ns; the minimum switched-on time was 150 ns for 60 ns on-off pulse separation. Furthermore it was possible to demonstrate repetitive switching with a minimum switching period of 1 mu s.