An integrated GaAs distributed-feedback oscillator–amplifier system

An investigation was made of an integrated pair consisting of a distributed-feedback oscillator and a travelingwave amplifier formed in a single-mode planar GaAs waveguide and pumped by an electron beam. Using this device, an output radiation power of 0.5 W was achieved in the single-mode regime with a low spontaneous noise level. A study of the spectral and power dependences of the superluminescence intensity on the lengths of the absorbing and amplifying sections of the waveguide was used to find the gain and absorption coefficients per unit length and their dependences on the radiation power density. The possibility of using this system as a radiation intensity modulator is discussed.