Seminar Announcement: Simone Normani
Data pubblicazione: 2-nov-2015 13.32.13
Monday, 26 October 2015, 11:00
Sala Grande Palazzina C via alla Cascata 56/C
"Multisite Excitation and Emission Properties of the Nd3+ and Lu3+ Doped CaF2 Laser Crystals"
Centre de recherche sur les Ions, les Matériaux et la Photonique (CIMAP), UMR 6252
CEA-CNRS-ENSICAEN, Université de Caen, 6 Blvd Maréchal Juin, 14050 Caen,
It was recently demonstrated that efficient and broadband laser emission was possible with Nd-doped CaF2 and SrF2 single crystals around 1.055 μm. Such laser emission, known as completely quenched because of cross-relaxation in the singly doped materials, increases spectacularly by co-doping with non-optically active ions like Y3+ or Lu3+. Broadband laser emission and ultra-short laser operation could be already demonstrated and large scale high peak power diode-pumped amplifiers can be anticipated. A deep investigation of both spectral and dynamical properties of CaF2:Nd3+ crystals co-doped with various amounts of Lu3+ was performed via conventional spectroscopy techniques: the results suggest that an increase in Lu3+ concentration tends to increase the efficiency of Nd3+ transitions, interpreted as a consequence of cluster breaking by the buffer ions. By employing the parameters from previous data, time-resolved spectroscopy has been employed in order to isolate the different centres: different spectra resulted from these measurements, and linear combinations of the two have been seen to recover fairly faithfully the different emission spectra at different co-doping levels and excitation wavelengths.
Keywords: Laser crystals; Spectroscopy; CaF2; Neodymium; Lutetium; Clustering.