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We report the synthesis and optical characterization of semipolar-oriented III-nitride quantum well (QW) structures obtained by growth on chemical vapor deposited graphene layers using metalorganic vapor phase epitaxy. Various multi-quantum well stacks of GaN(QW)/AlGaN(barrier) and InGaN (QW)/GaN (barrier) were grown. Growth on graphene not only helps achieve a semipolar orientation but also allows facile transfer of the QW multilayer stack to other cheap, flexible substrates. We demonstrate room-temperature photoluminescence from layers transferred to flexible Kapton films. [ABSTRACT FROM AUTHOR]

Abstract: We report the growth and characterization of group III-nitride semiconductor layers on graphene grown by chemical vapour deposition. GaN, AlGaN alloys, and InN layers are grown using an AlN nucleation and a buffer layer. We investigate the effect of varying growth temperature and V/III ratio and show that under optimized growth conditions preferentially semipolar oriented nitride layers can be obtained. These layers, though polycrystalline, are highly oriented and show strong room temperature photoluminescence, thus showing graphene to be a novel substrate for the growth of III-nitride materials. [Copyright &y& Elsevier]

Combining graphene with plasmonic nanostructures is currently being explored for high sensitivity biochemical detection based on the surface‐enhanced Raman scattering (SERS) effect. Here, a novel and tunable platform for understanding SERS based on graphene monolayers transferred on arrays of split ring resonators (SRRs) exhibiting resonances in the visible range is introduced. Raman enhancement factors per area of graphene of up to 75 are measured, demonstrating the strong plasmonic coupling between graphene and the metamaterial resonances. Apart from the incident laser light, both the photoluminescence signal emitted by the SRRs and the Raman scattered light from graphene contribute to the excitation of distinct resonances, resulting in different SERS. This new perspective allows control of SERS in the case of graphene on plasmonic metamaterials or nanostructures and potentially paves the way towards an advanced SERS substrate that could lead to the detection of single molecules attached to graphene in future biochemical sensing devices. [ABSTRACT FROM AUTHOR]