Multi-bandgap photonic materials and devices fabricated by UV-laser induced quantum well intermixing

Ultraviolet （UV）-laser induced quantum well intermixing （QWI） technique can generate large multiple bandgap blue shifts in Ⅲ-Ⅴ quantum well semiconductor heterostructure. The application of the UV-laser QWI technique to fabricate multi-bandgap photonic devices based on compressively strained InGaAsP/InP quantum well laser microstructure is reported. We show that under certain UV-laser irradiation conditions, the photoluminescence （PL） intensity can be enhanced, and the full width at half maximum （FWHM） linewidth can be reduced. The blue shift of bandgap can reach as large as 145 nm, while the PL intensity is about 51% higher than that of the as-grown material. Experimental results of post growth wafer level processing for the fabrication of bandgap-shifted waveguides and laser diodes are presented.