Gallium nitride on gallium oxide substrate for integrated nonlinear optics
KAUST DepartmentPhysical Sciences and Engineering (PSE) Division
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AbstractGallium Nitride (GaN), being a direct bandgap semiconductor with a wide bandgap and high thermal stability, is attractive for optoelectronic and electronic applications. Furthermore, due to its high optical nonlinearity — the characteristic of all 111-V semiconductors — GaN is also expected to be a suitable candidate for integrated nonlinear photonic circuits for a plethora of apphcations, ranging from on-chip wavelength conversion to quantum computing. Although GaN devices are in commercial production, it still suffers from lack of a suitable substrate material to reduce structural defects like high densities of threading dislocations (TDs), stacking faults, and grain boundaries. These defects significandy deteriorate the optical quality of the epi-grown GaN layer, since they act as non-radiative recombination centers. Recent studies have shown that GaN grown on (−201) β-Gallium Oxide (Ga<inf>2</inf>O<inf>3</inf>) has superior optical quality due to a better lattice matching as compared to GaN grown on Sapphire (Al<inf>2</inf>O<inf>3</inf>) [1-3]. In this work, we report on the fabrication of GaN waveguides on GaiOj substrate and their optical characterization to assess their feasibihty for efficient four-wave mixing (FWM).
CitationAwan KM, Dolgaleva K, Muhammed MM, Roqan IS (2017) Gallium nitride on gallium oxide substrate for integrated nonlinear optics. 2017 Photonics North (PN). Available: http://dx.doi.org/10.1109/PN.2017.8090587.
Journal2017 Photonics North (PN)
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