Steady-state characteristics of a $GaAs$ injection quantum amplifier receiving a narrow-band input signal

An investigation was made of the amplifying characteristics of a stripe homojunction laser in which positive feedback was suppressed by orienting the axis of the active region at an angle to the cleaved end faces. Radiation from a conventional cw stripe homojunction laser emitting a single mode was used as the input signal. An analysis was made of the output power and spectral characteristics of the amplifier as a function of the rate of pumping of the amplifier and of the amplitude of the input signal. It was found that the gain exceeded $10^3$ in the linear amplification regime and that the superradiant background was almost completely suppressed when the amplification process was saturated by a sufficiently strong input signal. An optical filter with a pass band 0,1 nm wide was placed at the amplifier exit and in this configuration the amplifier sensitivity was $0,4\cdot10^{-7}$ W.