The effect of IR radiation on generation in Gunn diodes

The effect of laser radiation with a quantum energy of about 0.12 eV on the generation characteristics of Gunn diodes has been studied experimentally over a wide range of bias voltages. It is found that amplitude-modulated IR radiation results in the modulation of the generation frequency of Gunn diodes. The extent of frequency modulation increases with the laser pulse length to a maximum of 0.6 F (where F is modulation frequency) and then decreases monotonically. The observed modulation is attributed to the thermal effect of IR radiation which results in reduced average electron velocity.