Nanoscale Optical Properties of Indium Gallium Nitride/Gallium Nitride Nanodisk-in-Rod Heterostructures

TitleNanoscale Optical Properties of Indium Gallium Nitride/Gallium Nitride Nanodisk-in-Rod Heterostructures
Publication TypeJournal Article
Year of Publication2015
AuthorsZhou, X, Lu, M-Y, Lu, Y-J, Jones, EJ, Gwo, jr, S, Gradecak, S
JournalAcs Nano
Volume9
Issue3
Pagination2868 - 2875
Date Published2015/03//
Abstract

III-nitride based nanorods and nanowires offer great potential for optoelectronic applications such as light emitting diodes or nanolasers. We report nanoscale optical studies of InGaN/GaN nanodisk-in-rod heterostructures to quantify uniformity of light emission on the ensemble level, as well as the emission characteristics from individual InGaN nanodisks. Despite the high overall luminescence efficiency, spectral and intensity inhomogeneities were observed and directly correlated to the compositional variations among nanodisks and to the presence of structural defect, respectively. Observed light quenching is correlated to type 11 stacking faults in InGaN nanodisks,,and the mechanisms for stacking fault induced nonradiative recombinations are discussed in the context of band structure around stacking faults and Fermi level pinning at nanorod surfaces. Our results highlight the importance of controlling III-nitride nanostructure growths to further reduce defect formation and ensure compositional homogeneity for optoelectronic device with high efficiencies and desirable spectrum response.