Triggerable semiconductor lasers

A triggerable semiconductor laser emits light in very short (0.1 nS) intense (0.1 W) pulses with a few nS period when biased a fraction of a mA above a threshold current. Single, uniform lightwave pulses can be triggered by fractional-mA current pulses up to several nS in duration. This behavior was first seen in computer simulations of devices with a high electron-trap density (other causes are possible). Devices exhibiting this behavior have been found among the population of AlGaAs stripe lasers made by deep proton bombardment. A simple lightwave pulse regenerator has been built by adding a photodiode with less than unity gain. This circuit emits lightwave pulses with 6 pJ energy, less than 0.2 ns duration, and with an amplitude that is up to 15 times larger than the input pulse.