Properties of ion-implanted high-power angled-grating distributed-feedback lasers

An improvement of the linearity of the light-current characteristics and the beam quality of high-power α-distributed feedback lasers is achieved by an ion implantation of the regions outside the contact stripe. The linear part of the light-current characteristics of 4-mm-long devices emitting at 1060 nm is extended to P=1.8 W output power. The times-diffraction-limit factor M
²
remains constant, equal to 1.7 over the whole power range. Simulations of the electro-optical behavior reveal that the improvement is achieved by a suppression of optical field components which propagate inside the cavity perpendicular to the facets.