High power single mode VCSEL operation with photo-active current channeling

Proposed on-axis current channeling through the use of photoactive layer(s) in vertical-cavity surface emitting laser (VCSEL) cavities counteracts hole burning and allows single mode operation at high currents. The photoactive layers act as variable resistivity screens whose radial 'aperture' is controlled by the light itself, providing an efficient feedback for mode control. Absorption of a small fraction of the light intensity suffices for significant on-axis current peaking with minimum efficiency loss and optical mode distortion. Fabrication is implemented during the molecular beam epitaxy phase without wafer post-processing, as for oxide apertures.