Therefore, the larger decay rate fluctuation is attributed to the fluctuations in the surface-plasmon excitation rate. Figure 5 Decay rate distributions SBI-0206965 order of nc-Si-SiO x structures with and without Au 5 nm layer. Other model used

for the statistical analysis of the time-resolved emission from the assembly of semiconductor quantum dots was proposed by van Driel et al. [21], which takes into consideration the log-normal distribution of decay rates. This model was used under studies of spontaneous emission decay rate, an assembly of Si nanocrystals in porous silicon (PSi) near semicontinuous gold films [22]. For the Au/PSi samples, the log-normal model gave a good fit with the experimental dates. It has been shown that PL decay rates also strongly modified

upon deposition of a thin Au film. The decay rate fluctuation in Au/PSi samples was related to the fluctuations in the LDOS. Conclusions We investigated the photoluminescence spectra of the silicon Ferrostatin-1 molecular weight nanoparticles, embedded into porous SiO x matrix, coated by Au-nanoisland layer. It has been shown that the spontaneous emission decay rate of the excited ncs-Si in the sample coated by Au nanoislands was accelerated. Close peak positions of the nc-Si emission and absorption of Au PF01367338 nanoparticles indicate that excitons generated in ncs-Si could effectively couple to the local surface plasmons excited at the surface of Au nanoparticles and increase the radiative recombination rate. We studied also the wavelength dependence of the PL decay rates in the samples with and without Au layer. The emission decay rate distribution was determined by fitting of the experimental over decay curves within frameworks of the stretched exponential model. It was supposed that for the Au-coated nc-Si-SiO x samples, the larger width in the decay rate distribution might be attributed to the fluctuations in the surface-plasmon excitation rate due to the uncertainty in the metal-emitter distance. Acknowledgements Authors are grateful to Dr. O.S. Litvin for the

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