21 research outputs found
Oxide phosphors for light upconversion; Yb3+ and Tm3+ co-doped Y2BaZnO5
Copyright 2011 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. This article appeared in Journal of Applied Physics 109, 063104 (2011) and may be found at
High power multimode fiber amplifier with wavefront reshaping for high beam quality recovery
International audienc
Spatial mode control of a diode-pumped Nd:YAG laser by use of an intracavity holographic phase plate
International audienceWe present a new method of realizing phase plates by phase-volume holography on a photopolymer film. We implement such a component in a diode-pumped Nd:YAG oscillator to control the output spatial beam profile. Flattop super-Gaussian and square-shaped beams are obtained
High energy, single-mode, narrow-linewidth fiber laser source using stimulated Brillouin scattering beam cleanup
International audienceWe propose an original nonlinear beam cleaning fiber laser architecture to obtain high energy pulses with a good beam quality and a narrow linewidth. The output beam of a large core Er:Yb co-doped multimode fiber amplifier (M2 ~ 6, 220 ÎĽJ) is converted into a near diffraction limited beam (M2 = 1.6) through a stimulated Brillouin scattering injection seeded beam cleanup process. We report in this experiment a multimode to single mode conversion efficiency of 50% while preserving the master oscillator linewidt
Synthesis and Characterizations of YVO<sub>4</sub>:Eu Colloids
International audienceWe present a new process for the synthesis of colloidal europium-doped yttrium vanadate with a particle diameter of about 10 nm. Nanocrystals are produced by precipitation of citrate complexes of rare-earth salts with sodium orthovanadate. NMR and IR studies show that the interaction between citrate ligands and lanthanide ions limits the growth of particles and ensures the stability of the colloidal solutions through electrostatic and steric repulsions. The optimized process leads to stable and highly concentrated transparent colloidal solutions in water (up to 400 g‚L-1)
High Energy, Single-Mode, Narrow-Linewidth Fiber Laser Source with Stimulated Brillouin Scattering Multimode to Single Mode Beam Converter
International audienceWe study a new nonlinear beam cleaning fiber laser architecture to obtain high energy polarized pulses with a good beam quality and a narrow linewidth, which is very attractive for fiber-based coherent lidar applications. The set-up involves stimulated Brillouin scattering in an injection seeded arrangement to proceed the cleanup of an aberrated wavefront coming from a large core Er:Yb co-doped fiber amplifier, operating at 1.55 ÎĽm. Both theoretical and experimental results are presented, and we report the conversion of a multimode depolarized beam into a near diffraction limited polarized beam with an efficiency of 50%, while preserving the master oscillator linewidth
Principles and optimisation of Rh :BaTiO3 phase conjugators and their application to MOPA lasers
International audienc
Principles and optimisation of Rh :BaTiO3 phase conjugators and their application to MOPA lasers
International audienc