Observation of single-mode oscillation in gain-guided GaAlAs laser array

A single-longitudinal-mode oscillation has been observed for the gain-guided GaAlAs laser arrays under controlled conditions. These multiple-element laser arrays were operated under continuous-wave conditions with controllable temperatures and currents. We have observed single-longitudinal-mode operation at near threshold and above threshold for operating temperatures of 10–37 °C. A mode intensity ratio of over 50:1 was observed with fairly stable output. In addition, a single-lobed far-field pattern under single-mode oscillation was also observed.