Mixed sesquioxides are a very promising class of laser materials, in particular for applications requiring ultrashort pulse generation or broadband tuning. The disordered crystalline structure of these materials determines a significant broadening of the emission spectra with respect to the pure com-pounds such as Yb:Sc2O3, Yb:Y2O3 and Yb:Lu2O3 [1]. We investigated the spectroscopic properties and the laser performances of Yb:(LuXY(1-x))2O3 ceramics with different Y/Lu balances. The nanoparticles of these solid solutions were produced by laser ablation method. The synthesized nanopowders were uniaxially pressed at 200 MPa into Ø15 mm cylindrical pellets. After removing the organic components by annealing at 800 °C for 3 h in air, the green pellets were sintered at 1780 °C for 20 h under 10-3 Pa vacuum, The obtained ceramic samples were then annealed at 1400 °C for 2 h in air to eliminate the oxygen vacancies. We measured the absorption and emission cross section spectra of Yb3+ (in particular the impact of the Y/Lu balance on the emission spectrum) and its upper level lifetime. Samples microstructure was characterized by means of XRD, optical microscopy and SEM, and the influence of the different Y/Lu balance was assessed. Laser tests were carried out in an end pumped confocal cavity, using a fiber coupled laser diode emitting at 936 nm as pump source. We obtained a maximum output power of 3.9 W, with a slope efficiency of about 50% and an optical to optical efficiency of 41% in quasi-CW pumping regime, using a sample of 5% Yb:(Lu0.15Y0.85)2O3 ceramic. The tunability of the ceramic was explored, finding a tuning range as large as 90 nm (from 1000 nm to 1090 nm), with two main emission peaks at 1030 nm and 1075 nm.
Yb DOPED (LuxY(1-x))2O3 MIXED SESQUIOXIDE CERAMICS: FABRICATION, SPECTROSCOPY AND LASER EMISSION
G Toci;A Pirri;B Patrizi;M Vannini;
2017
Abstract
Mixed sesquioxides are a very promising class of laser materials, in particular for applications requiring ultrashort pulse generation or broadband tuning. The disordered crystalline structure of these materials determines a significant broadening of the emission spectra with respect to the pure com-pounds such as Yb:Sc2O3, Yb:Y2O3 and Yb:Lu2O3 [1]. We investigated the spectroscopic properties and the laser performances of Yb:(LuXY(1-x))2O3 ceramics with different Y/Lu balances. The nanoparticles of these solid solutions were produced by laser ablation method. The synthesized nanopowders were uniaxially pressed at 200 MPa into Ø15 mm cylindrical pellets. After removing the organic components by annealing at 800 °C for 3 h in air, the green pellets were sintered at 1780 °C for 20 h under 10-3 Pa vacuum, The obtained ceramic samples were then annealed at 1400 °C for 2 h in air to eliminate the oxygen vacancies. We measured the absorption and emission cross section spectra of Yb3+ (in particular the impact of the Y/Lu balance on the emission spectrum) and its upper level lifetime. Samples microstructure was characterized by means of XRD, optical microscopy and SEM, and the influence of the different Y/Lu balance was assessed. Laser tests were carried out in an end pumped confocal cavity, using a fiber coupled laser diode emitting at 936 nm as pump source. We obtained a maximum output power of 3.9 W, with a slope efficiency of about 50% and an optical to optical efficiency of 41% in quasi-CW pumping regime, using a sample of 5% Yb:(Lu0.15Y0.85)2O3 ceramic. The tunability of the ceramic was explored, finding a tuning range as large as 90 nm (from 1000 nm to 1090 nm), with two main emission peaks at 1030 nm and 1075 nm.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
