Conference Agenda

Transparent ceramics of Holmium-doped yttria (Ho:Y2O3) were fabricated by Hot Isostatic Pressing at 1720 °C / 190 MPa in argon, and the effect of YF3 addition on their microstructure, optical, vibronic and infrared emission properties was studied. The fluorine addition improves the ceramic transparency, accelerates the grain growth and enhances the luminescence lifetimes of Ho3+ states responsible for emissions at 2 µm and 3 µm.

In the context of the quest of organic laser diode, we propose a method to compare organic gain semiconductors in terms of laser threshold before integrating them into laser cavity. This method is based on three types of measurements for each material: 1-measurements of absorption and photoluminescence spectra to evaluate the re-absorption, 2-measurement of fluorescence lifetimes linking the potential laser gain to the current in the diode and 3-measurement of the gain of the amplified spontaneous emission. This approach is validated by laser threshold measurements carried out under optical pumping for two organic compounds DCM and DCJTB deposited on laser cavities

We report on a comprehensive spectroscopic study of singly Dy3+ doped and Er3+,Dy3+ codoped calcium fluoride (CaF2) crystals for midinfrared laser applications. The f-f transition probabilities of Dy3+ were determined by the Judd-Ofelt theory. The stimulated-emission cross-section reaches 0.25×10-20 cm2 at 2.93 µm corresponding to an emission bandwidth of 350 nm. The Er3+ → Dy3+ energy transfer efficiency in codoped crystals is quantified. The 4.4-µm Dy3+ emission is observed for the first time from fluorite crystals.

Surface-doping of lithium niobate wafers with rare earth or optically damage-resistant ions by physical vapour deposition and high-temperature in-diffusion is a cost-efficient and flexible method for the fabrication of thin-film LN or LNOI with dopants which are not common in crystal growth. LNOI doped with different concentrations of Er, Yb, Tm, Pr, Zn and Zr has been fabricated. As an example, the fluorescence spectra of Er:Yb:LNOI samples were recorded, and a high small-signal gain of 35 dB/cm was measured in ridge waveguides.

The objective of this work is to design a secondary luminescent concentrator (LC) -optically pumped by a YAG:Ce primary luminescent concentrator- then emitting photons between 1.0 and 1.5 µm in the SWIR. The main properties should be a good overlap of the absorption spectrum with the YAG:Ce emission, a high quantum efficiency value for the Ni2+ emission, and a good optical quality of the crystal to limit losses. Ni2+ doped lasers crystal such as LaMgAl11O19:Ni and YAlO3:Ni or LiGa5O8:Ni glass-ceramics can be proposed and are investigated within this work.

Lanthanum oxysulfide powders doped with Erbium ions were fabricated by the combustion method followed by sulfurization at 1000 °C under H2S + N2 atmosphere. X-ray diffraction confirms their single-phase nature (sp. gr. P-3m1). Raman spectroscopy reveals a maximum phonon energy of 389 cm-1. The effect of Er3+ doping level (0.5 – 7 mol%) on the visible and mid-infrared emission properties of Er:La2O2S was studied.