Optical response of a stripe-geometry junction laser to sinusoidal current modulation at 1.2 GHz

Measurements of the intensity modulation induced on the optical output of a proton-bombarded stripe-geometry junction laser by sinusoidal modulation of the laser current at 1200 MHz are reported. Emission occurs in short pulses at any bias current if the current modulation is sufficiently Strong, but only at bias currents which place the laser´s internal resonance in the vicinity of one half or one times the modulating frequency if the current modulation is weak. The apparent threshold for lasing is shown to decrease when the RF modulation depth reaches 100 percent, but linearity of the current dependence of the average output power is not maintained at high optical power levels.