Color tunability of intense upconversion emission from Er3+–Yb3+ co-doped SiO2–Ta2O5 glass ceramic planar waveguides

Abstract

This work reports on the infrared-to-visible CW frequency upconversion from planar waveguides based on Er 3+ -Yb 3+ -doped 100-xSiO 2 -xTa 2 O 5 obtained by a sol-gel process and deposited onto a SiO 2 -Si substrate by dip-coating. Surface morphology and optical parameters of the planar waveguides were analyzed by atomic force microscopy and the m-line technique. The influence of the composition on the electronic properties of the glass-ceramic films was followed by the band gap ranging from 4.35 to 4.51 eV upon modification of the Ta 2 O 5 content. Intense green and red emissions were detected from the upconversion process for all the samples after excitation at 980 nm. The relative intensities of the emission bands around 550 nm and 665 nm, assigned to the 2 H 11/2 / 4 I 15/2 , 4 S 3/2 / 4 I 15/2 , and 4 F 9/2 / 4 I 15/2 transitions, depended on the tantalum oxide content and the power of the laser source at 980 nm. The upconversion dynamics were investigated as a function of the Ta 2 O 5 content and the number of photons involved in each emission process. Based on the upconversion emission spectra and 1931CIE chromaticity diagram, it is shown that color can be tailored by composition and pump power. The glass ceramic films are attractive materials for application in upconversion lasers and near infrared-to-visible upconverters in solar cells.

Synthesis, characterization and evaluation of scintillation properties of Eu3+-doped Gd2O3 obtained using PEG as precursor

“…[1] Among the materials that are promising for these applications, those that contain rare earth (RE 3+ ) ions in their compositions are of special interest. Materials containing RE 3+ ions have been studied and excellent photoluminescent results have been obtained due to its upconversion [2][3][4] and downconversion [5][6][7] properties.…”

Er3+-doped fluorotellurite thin film glasses with improved photoluminescence emission at 1.53 µm

“…Different chemical and physical methods have been attempted to produce RE doped thin film glasses such as sol-gel, chemical vapor deposition, sputtering or pulsed laser deposition (PLD) [21,22,23,24,25]. In particular, PLD has demonstrated to be a very versatile technique to produce thin films and it has been successfully applied to the synthesis of good quality tellurite, oxyfluoride silicate or phospho-tellurite glasses having a complex stoichiometry [24,26,27,28].…”

Desenvolvimento de materiais nanoestruturados à base de SiO2-Nb2O5 preparados por uma nova rota sol-gel com aplicações em fotônica

“…Em trabalhos anteriores de nosso grupo foi verificado que os alcóxidos utilizados como precursores na preparação de materiais dopados com íons TR por sol-gel foram muito sensíveis à hidrólise FERRARI et al, 2012;AQUINO, 2013;AQUINO et al, 2014;AQUINO et al, 2016). Alquier et al (ALQUIER et al, 1986) também reportaram a dificuldade em se preparar géis de pentóxido de nióbio devido à rápida hidrólise do precursor etóxido de nióbio.…”