Towards sub-300 nm AlGaN laser diodes on bulk AlN substrates
We report recent progress on the development towards sub-300 nm laser diodes. By using high-quality bulk AlN substrates we are able to achieve excellent crystalline quality of the epitaxially grown MOCVD laser hetero-structures. We successfully realized optically pumped AlGaN-based lasers in the wavelength regime between 237 and 291nm with threshold pump power densities below 130 kW/cm2. Results of structural and optical investigation methods will confirm the high material quality, which led to the high lasing performance. We will discuss the polarization properties of the lasers with different emission wavelengths and present concepts of how to address the electrical challenge of high bandgap laser diodes.
Wunderer, T.; Chua, C. L.; Northrup, J. E.; Yang, Z.; Johnson, N. M.; Kneissl, M.; Garret, G. A.; Shen, H.; Wraback, M.; Moody, B.; Craft, H.; Schlesser, R.; Dalmau, R.; Sitar, Z. Towards sub-300 nm AlGaN laser diodes on bulk AlN substrates. Spring Meeting of the German Physical Society; 2012 March 25-30; Berlin, Germany.