We investigated and demonstrated a 1.3 μm-band laser grown by metalorganic vapour phase epitaxy (MOVPE) on a specially engineered metamorphic parabolic graded InxGa1−xAs buffer and epitaxial structure on a GaAs substrate. Bottom and upper cladding layers were built as a combination of AlInGaAs and InGaP alloys in a superlattice sequence. This was implemented to overcome (previously unreported) detrimental surface epitaxial dynamics and instabilities: when single alloys are utilised to achieve thick layers on metamorphic structures, surface instabilities induce defect generation. This has represented a historically limiting factor for metamorphic lasers by MOVPE. We describe a number of alternative strategies to achieve smooth surface morphology to obtain efficient compressively strained In0.4Ga0.6As quantum wells in the active layer. The resulting lasers exhibited low lasing threshold with total slope efficiency of 0.34 W/A for a 500 μm long ridge waveguide device. The emission wavelength is extended as far as 1360 nm.
@article{arxiv.2103.08267,
title = {The importance of overcoming MOVPE surface evolution instabilities for >1.3 $\mu$m metamorphic lasers on GaAs},
author = {Enrica E. Mura and Agnieszka M. Gocalinska and Megan O'Brien and Ruggero Loi and Gediminas Juska and Stefano T. Moroni and James O'Callaghan and Miryam Arredondo and Brian Corbett and Emanuele Pelucchi},
journal= {arXiv preprint arXiv:2103.08267},
year = {2021}
}