A novel optoelectronic closing and opening switch for pulsed power

The bulk optically controlled semiconductor switch (BOSS), which can be turned on and off on command by laser light at two different wavelengths, is discussed. The switch is essentially bistable, as it retains its high conductivity after turn-on for times long compared to the duration of the exciting (turn-on) laser light. The turn-on and turn-off time constants can be as short as several hundred picoseconds. According to the results of a rate equation model for the switch, currents in the kiloampere range can be controlled with a laser power density of less than 10 MW/cm², making these switches suitable for pulsed power applications. The feasibility of the BOSS concept has been demonstrated with GaAs:Si,Cu as the switch material. Optically controlled closing and opening has been achieved on a nanosecond time scale