m -plane pure blue laser diodes with p-GaN/n-AlGaN-based asymmetric cladding and InGaN-based wave-guiding layers

Asymmetric p-GaN/n-AlGaN-cladded InGaN-based pure blue (440–460 nm) laser diodes were fabricated based on the nonpolar m-plane GaN technology. Simulation results showed high indium content (5%–10%) InGaN wave-guiding layers mainly contributed to the optical confinement, so that n-AlGan layer can be used to control of the peak position of the optical mode to achieve high optical confinement factor and low internal loss. By using this laser structure, lasing wavelengths of 443 and 465 nm with threshold current densities 14 and 19 kA/cm2, respectively, were demonstrated without facet coating.