The study of amorphous phase-separated Dielectric Nano-Particles (DNPs) smaller than 10 nm is a great challenge for the materials community. In conjunction with Transmission Electron Microscopy (TEM) and Electron-Probe Micro-Analysis (EPMA), we took advantage of a recent technology, Tri-Dimensional (3D) Atom Probe Tomography (APT) to investigate the variations of the chemical composition in sub-20-nm oxide nanoparticles, grown in silicate glass through heat treatments, at their early stages of nucleation. More precisely, we are investigating the core of an optical fiber drawn from a preform prepared according to the Modified Chemical Vapor Deposition (MCVD) process. We provide here a comprehensive set of experimental data obtained from direct measurements of the concentration for P, Mg, Ge and Er within amorphous dielectric nanoparticles (DNP) of radii ranging from 1 nm to 10 nm. We report on an increase of the concentration of Mg and P with the size of the DNPs. Most importantly, we also demonstrate that erbium ions are partitioned in these small DNPs and their environment changes with the size of the nanoparticles. Molecular dynamics simulations were also implemented to discuss the structural modifications of the Er environment. This presentation highlights the trade off on the size of the DNPs: smaller to reduce light scattering vs bigger to modify luminescence properties.
Formation of rare-earth doped nanoparticles into silica matrix has been modelized by Molecular Dynamics simulations. Preforms with molar composition 0.10MgO–0.90SiO2 and 0.01EuO3/2–0.10MgO–0.89SiO2 have been investigated to have an insight on the structure and chemical composition of the nanoparticles, as well as the rare-earth ions local environment and their clustering. We have finally applied a uniaxal elongation of the rare-earth doped preform in order to mimic the drawing step that changes a preform into a fiber. We present herein first results on the modification of the nanoparticles size distribution.
Lasers and amplifiers based on thulium-doped silica fibers require improved spectroscopic properties. In this context, one of the most promising approaches is based on the embedding of thulium ions in nanoparticles of tailored composition and structure. This paper presents various methods used to produce thulium-doped nanoparticles inside silica-based optical fibers. Effects of solution doping method during the elaboration of Modified Chemical Vapor Deposition preform and doping solution composition are studied. A comparison is made between the use of solutions containing LaF3:Tm3+ or YAG:Tm3+ nanoparticles and aluminum-lanthanum-thulium chlorides. Results show that for similar lanthanum content, lanthanum-thulium chlorides doping allows for similar enhancement of 3H4 level of Tm3+ than LaF3:Tm3+ doping. Also, effects of aluminum on 3H4 lifetime enhancement and inhibition of nanoparticle’s formation is discussed.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.