Cooperative upconversion luminescence of Er3+ in Gd2O3-xSx phosphor

Comparative study on the photoluminescence properties of monoclinic and cubic erbium oxide

As a heavy rare earth oxide, erbium oxide (Er₂O₃) has many attractive properties. Monoclinic Er₂O₃ has useful properties not found in stable cubic Er₂O₃, such as unique optical properties and high radiation damage tolerance. In this study, pure cubic and mixed phase of cubic and monoclinic Er₂O₃ coatings were prepared. Photoluminescence properties of these coatings were characterized by a confocal micro-Raman spectrometer equipped with 325, 473, 514, 532, 633 nm lasers, and the influence of microstructure on the fluorescence properties was analyzed in detail. The room temperature fluorescence peaks of cubic Er₂O₃ were assigned. Furthermore, a novel method for rapid phase identification of Er³⁺ doped cubic and monoclinic rare earth sesquioxides at room temperature was proposed.

Thermometry properties of Er, Yb-Gd2O2S microparticles: dependence on the excitation mode (cw versus pulsed excitation) and excitation wavelength (980 nm versus 1500 nm)

Herein, we present a first report on the luminescence thermometry properties of Er, Yb doped Gd₂O₂S microparticles under near infrared up-conversion excitation at 980 and 1500 nm measured in the 280-800 K interval. The thermometry properties are assessed using both cw and ns pulsed excitation as well as tuning the excitation wavelength across Yb and Er absorption profiles. For low cw (300 mW cm^-1) and pulsed ns (400 ÷ 550 mW cm^-1) excitation modes, no thermal load is observed. At room-temperature (280 K), the maximum relative sensitivity values are comparable under pulsed excitation at 980 and 1500 nm, around ∼0.01 and ∼0.008% K^-1, respectively. In addition, a relative intense up-conversion emission at 980 nm under excitation at 1500 nm is measured. Our findings evidence attractive up-conversion and thermometry properties Er, Yb doped Gd₂O₂S under near-infrared excitation and highlight the need to explore further these properties in the nanoparticulate regime.