Semiconductor InGaAs/GaAs injection lasers with waveguides based on a single quantum well

Semiconductor InGaAs/GaAs injection lasers emitting at $\lambda$ = 1065 nm have been created with waveguides based on a single InGaAs quantum well. It is found that internal optical losses are determined by the width of an undoped region confined between the $n$ and $p$ type emitters. The room-temperature total output optical power in lasers with 100 $\mu$m aperture amounted up to about 2 W at a radiation beam divergence of 15$^\circ$ in the plane perpendicular to the $p$–$n$ junction.