Optical characteristics of high-power nonplanar periodic laser arrays

The authors describe nonplanar arrays, grown by metalorganic chemical vapor deposition, that consist of a periodic array of mesas and grooves, which provides index guiding and prevents lateral lasing. The near- and far-field patterns are shown to be a strong function of the laser structure, particularly of the confining layer composition and effective index step. The near-field pattern determined by the structure affects the external differential quantum efficiency of these arrays relative to similar planar active region devices. Laser emission was generally confined to the mesa regions. A simple model is used as an aid to explain the observed near- and far-field patterns and to identify the mechanisms which confine the optical field to the mesa or groove region