Sychugov, IlyaGaleckas, AugustinasElfström, NiklasWilkinson, Andrew R.Elliman, Robert G.Linnros, Jan2015-11-032015-11-030003-6951http://hdl.handle.net/1885/16216The influence of the proximity of a high refractive index substrate on the luminescence of Si nanocrystals was investigated by time-integrated and time-resolved photoluminescence. The luminescence yield was found to be ∼2.5 times larger for emitters distanced from the substrate compared to those in proximity with the substrate, while luminescence decay measurements revealed only a slight increase in the luminescence lifetime (∼15%). Results are discussed in terms of local density of optical modes surrounding a pointlike light emitter with important implications for the collection efficiency of luminescence and the estimation of internal quantum efficiency for a quantum dot.Support for this work was provided by the Swedish Research Council VR and the Australian Research Council ARC.http://www.sherpa.ac.uk/romeo/issn/0003-6951..."Publishers version/PDF may be used on author's personal website, institutional website or institutional repository" from SHERPA/RoMEO site (as at 3/11/15). Copyright 2006 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Applied Physics Letters and may be found at https://doi.org/10.1063/1.2226976Keywords: Density (optical); Photoluminescence; Quantum efficiency; Refractive index; Semiconductor quantum dots; Silicon; Luminescence decay measurements; Luminescence lifetimes; Si nanocrystals; Time-resolved photoluminescence; Nanostructured materials2006-09-1510.1063/1.22269762015-12-08