E′ and B2 center production in amorphous quartz by MeV Si and Au ion implantation

Samples composted of chemically synthesized Au nanoparticles (NPs) (16.0±2.0 nm) embedded within a planar silica film are used as model system to investigate the evolution of a second phase under irradiation when the temperature and the ion stopping power are changed. Samples are irradiated with 4 MeV Au2+ ions and 4 MeV Br2+ ions for temperature ranging from 30 °C up to 800 °C and for fluences up to 8×1016 cm−2. We show that at room temperature the complete dissolution of the NPs leads to the formation of smaller precipitates with a narrower size distribution, i.e., 2.0±0.3 nm. However, when the temperature is increased and/or the nuclear stopping power is decreased, a reduction in the dissolution rate was observed. This leads to the formation of a bimodal size distribution. Finally, the evolution of the density of the precipitates with the temperature is discussed in term of the thermal stability of the irradiation-induced defects within the silica matrix.

Section: B Contribution Of the Stopping Power On The Evolution On Thsupporting

confidence: 89%

Section: B Contribution Of the Stopping Power On The Evolution On Thmentioning

confidence: 99%

Controlling the size distribution of embedded Au nanoparticles using ion irradiation

Ramjauny

Rizza

Perruchas

et al. 2010

“…The crossover between these two regimes can be accounted for by considering the mobility of the defects within the host matrix. Indeed, the transition temperature is in agreement with the existing results indicating that irradiationinduced defects become mobile above 750-800 K. [33][34][35][36][37][38][39][40][41][42] The experimental data are fitted using the Dienes and Damask model. 37 The latter predicts the existence of two temperature regimes for the diffusion.…”

Section: A Diffusion Coefficient Under Irradiation D I ðT þsupporting

confidence: 83%

On the evolution of the steady state in gold-silica nanocomposites under sustained irradiation

Ramjauny

Hayoun

et al. 2015

“…PL spectra were measured with excitation at 250 nm to allow detection of photoluminescence from defects produced in the silica matrix after ion implantation. [35][36][37] We measured the photoluminescence versus excitation pump pulse fluence at 355 nm for the samples with Ptncs (samples A(RA) and C(RA)). We monitored the maxima of the PL spectra every 1 s over 1 min, for each excitation pump pulse fluence.…”

Section: Methodsmentioning

confidence: 99%

Platinum nanoclusters in silica: Photoluminescent properties and their application for enhancing the emission of silicon nanocrystals in an integrated configuration

Bornacelli

Silva-Pereyra

Rodrı́guez-Fernández

et al. 2016

We studied photoluminescence of ion implanted platinum nanoclusters embedded in silica. Pt ions were implanted at 2 MeV and the Pt nanoclusters were then nucleated by thermal treatment under either argon, air, or a reducing atmosphere of hydrogen and nitrogen. The nanoclusters showed broad photoluminescence spectra (400 to 600 nm) with a maximum intensity at 530 nm. The photoluminescence intensity of the Pt nanoclusters was sensitive to the ion fluence used during the ion implantation, and luminescence quenching was observed in samples fabricated at high Pt-ion fluence. A hybrid system composed of silicon nanocrystals and platinum nanoclusters embedded in a silica matrix was also made. The photoluminescence of the hybrid system spanned the entire visible spectrum, and emission from the silicon nanocrystals was enhanced. Published by AIP Publishing.