2011 Volume 8 Issue 2 Pages 109-113
We report on the high-power lasing characteristics of a large area bottom-emitting vertical-cavity surface-emitting laser (VCSEL). There have been difficulties in uniform current injection for large area VCSELs, which are caused by the band discontinuity at the interface between AlAs and GaAs of the n-type Distributed Bragg Reflector (DBR). We have reported the n-type DBR using a graded composition interface of 20nm thick suppresses the crowding of current to the edge of emitting area and improves external efficiency . The highest peak pulsed power of over 49W was achieved by a five-quantum-well VCSEL with a current aperture diameter of 200µm.