The Nd-nanocluster coupling strength and its effect in excitation/de-excitation of Nd 3+ luminescence in Nddoped silicon-rich silicon oxide Appl. Phys. Lett. 83, 2778Lett. 83, (2003 We report on the microstructure and photoluminescence ͑PL͒ properties of Nd-doped SiO 2 thin films containing silicon nanoparticles ͑Si-np͒ as a function of the annealing temperature and the Nd concentration. The thin films, which were grown on Si substrates by reactive magnetron co-sputtering, contain the same Si excess. Fourier transform infrared ͑FTIR͒ spectra show that a phase separation occurs during the annealing due to the agglomeration of the Si excess resulting in the formation of Si-np. Besides, after annealing, the films exhibit PL from excitonic states confined in Si-np. We showed that the intensity of the PL of Nd 3+ ions that occurs at ϳ0.92, 1.06, and 1.4 m is maximal at low Nd concentration and while well-passivated Si-np are formed. FTIR and x-ray measurements showed that the increase in the Nd incorporation has detrimental effects on the PL of Nd 3+ because of the formation of Nd 2 O 3 nanocrystals and inherent disorder in the SiO 2 host matrix. PL excitation measurements demonstrate that the PL of Nd 3+ ions is nonresonant and follows the excitation of Si-np giving new evidence of the energy transfer from Si-np toward the rare earth ions.

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