Fabry-Perot microcavity modes observed in the micro-photoluminescence spectra of the single nanowire with InGaAs/GaAs heterostructure

We report on the fabrication of the nanowires with InGaAs/GaAs heterostructures on the GaAs(111) B substrate using selective-area metal organic vapor phase epitaxy. Fabry-Perot microcavity modes were observed in the nanowires with perfect end facets dispersed onto the silicon substrate and not observed in the free-standing nanowires. We find that the calculated group refractive indices only considering the material dispersion do not agree with the experimentally determined values although this method was used by some researchers. The calculated group refractive indices considering both the material dispersion and the waveguide dispersion agree with the experimentally determined values well. We also find that Fabry-Perot microcavity modes are not observable in the nanowires with the width less than about 180 nm, which is mainly caused by their poor reflectivity at the end facets due to their weak confinement to the optical field. (C) 2009 Optical Society of America

Grant-in-Aid for Scientific Research Japan Society of Promotion of Science (JSPS) National Natural Science Foundation of China 60877015 90604001National High Technology Research and Development Program of China 2007AA03Z420 This work is partly financially supported by a Grant-in-Aid for Scientific Research and is also supported by the Japan Society of Promotion of Science (JSPS). L. Yang also thanks the support from National Natural Science Foundation of China under the Grant No. 60877015 and 90604001, and by the National High Technology Research and Development Program of China under Grant No. 2007AA03Z420.