Single-beam and single-mode emission from surface emitting laser diodes based on surface mode emission

Surface emitting laser diodes are of great interest for many optoelectronic applications, like optical interconnects, optical computing and high power laser arrays. We have developed a new concept, which provides both an efficient surface emission with low beam divergence as well as a mode selection mechanism from conventional horizontal cavity laser diodes. This concept is based on an interactive coupling process between the laser mode and a surface mode propagating in a waveguide on top of the laser diode. We report for the first time on a single beam and single mode emission that we have achieved from surface-mode-emitting-(SME)-laser diodes. The crucial advantage of the SME-type of laser diode, as compared to surface emitting DBR- or DFB-laser diodes, is a simple and flexible fabrication process. It utilises the well established technique of the conventional striped laser and requires no regrowth. It has been found that the emission wavelength and emission angle depend on the waveguide parameters, which are the thickness and the refractive index. This is a direct consequence of the SME-technique and can be explained by our model.