Lattice-Matched GaN-InAlN Waveguides at \lambda=1.55\ \mum Grown by Metal-Organic Vapor Phase Epitaxy

• Published in: IEEE photonics technology letters Vol. 20; no. 2; pp. 102 - 104
• Main Authors: Lupu, A., Julien, F.H., Golka, S., Pozzovivo, G., Strasser, G., Baumann, E., Giorgetta, F., Hofstetter, D., Nicolay, S., Mosca, M., Feltin, E., Carlin, J.-F., Grandjean, N.
• Format: Journal Article
• Language: English
• Published: IEEE 15.01.2008
• Subjects: Epitaxial growth; Gallium nitride; GaN; High speed optical techniques; intersubband (ISB) devices; Optical buffering; optical communication; Optical devices; Optical materials; Optical refraction; Optical saturation; optical waveguide (WG); Optical waveguides; Propagation losses
• ISSN: 1041-1135; 1941-0174
• DOI: 10.1109/LPT.2007.912551

We report on the demonstration of low-loss, single-mode GaN-InAlN ridge waveguides (WGs) at fiber-optics telecommunication wavelengths. The structure grown by metal-organic vapor phase epitaxy contains AlInN cladding layers lattice-matched to GaN. For slab-like WGs propagation losses are below 3 dB/mm and independent of light polarization. For 2.6-mum-wide WGs the propagation losses in the 1.5- to 1.58-mum spectral region are as low as 1.8 and 4.9 dB/mm for transverse-electric- and transverse-magnetic-polarization, respectively. The losses are attributed to the sidewall roughness and can be further reduced by the optimization of the etching process.