Beam Mode Observation in Quasi-Stadium Laser Diodes

We fabricated quasi-stadium laser diode which has a ´window´ on the top of cavity by ion-etching technique to epitaxial wafer and demonstrated to observe direct lasing mode observation. In the carrier poor region, bright line can recognize. On the other hands, in the rich carrier region, lasing pattern was recognized as dark line. Both lines well fit extended Fox-Li simulation. From these results, it can understand that the lasing pattern condition depend the carrier density.