Abstract

Recent development in high-power single mode semiconductor lasers has stimulated in the evaluation of several types of semiconductor laser amplifiers [1], [2]. Flared semiconductor laser amplifiers have demonstrated the highest output power with extremely good spatial coherence. However, the output near-field intensities have two side peaks [2], which may cause some problems. For example, they may excite higher-order modes in side-pumping solid-state lasers. Therefore, we propose a new flared structure that could significantly eliminate the two side peaks. The conventional flared amplifiers consist of a linearly tailored gain region that serves as the spherical (circular) expansion of the wave front. The expansion is not ideal because the beam mode has a nonzero beam size instead of being like a point source. The proposed hyperbolically flared structure analogizes the expansion of a Gaussian beam and therefore is better for the beam expansion.

© 1996 IEEE