In this thesis, using Micro-Photoluminescence (£g-PL), continuous-wave time-resolved photoluminescence (CWPL/TRPL) and Fourier transform infrared (FTIR) analysis, silicon rich nc-Si (nano-crystal Silicon) samples with various emission wavelength (760 30 nm and 390 10 nm) are investigated to understand the proper explanation of the emission mechanism. The model of increasing Si¡ÐO ¡ÐSi bondings during thermal process by enhancing the annealing or deposition time, induced blue shifts in PL spectrums and increased the rate of Schockley-Read-Hall recombination which resulted in the enhancement of its fluorescence is provided.

This thesis focus on the epitaxial growth and optical characterization of diluted InAs/InP(001) quantum dots for the realisation of new nanophotonic devices emitting at 1.55 [micro]m. The structural and optical properties of the quantum islands are correlated to different growth parameters of a solid source molecular beam epitaxy system. Our results highlight the influence of InAs surface reconstructions on the island shape. Dots rather than elongated dashes usually observed can be directly formed by adequate growth conditions. Dash to dot shape transition is also demonstrated by post-growth treatments. Low dot densities are obtained for small InAs deposited thickness. Their emission wavelength is easily tuned to 1.55 [micro]m using the"double cap" procedure for the growth of the InP capping layer. Optical properties of such single InAs/InP quantum dots are then evaluated. Micro-photoluminescence studies reveal sharp and well separated emission lines near 1.55 [micro]m from single dots confirming their atom-like properties. Last, we propose for the first time a high spatial resolution method to study the carrier transport in the vicinity of a single quantum dot using a low-voltage cathodoluminescence technique. A direct measurement of the carrier diffusion length before capture into one dot has been obtained. These results open the way to the integration of these single dots into optical micro-cavities for the realisation of quantum light sources at 1.55 [micro]m.