Optical, spectroscopic properties and Judd-Ofelt analysis of Nd3+-doped photo-thermo-refractive glass

A comparative study of spectral-luminescent and Judd-Ofelt analysis of photo-thermo-refractive (PTR) glasses doped with a variable content of neodymium (0.5-2.11 mol%) has been carried out for the first time. The change of Judd-Ofelt parameters (Omega(2), Omega(4), Omega(6)), radiation lifetime, experimental lifetime, branching ratio and emission cross sections were demonstrated as a function of Nd2O3 concentration and compared to the equivalent parameters in other works. It was found that the F-4(3/2) -> I-4(11/2) transition is enhanced in Nd-doped PTR glass. The quantum efficiency of 0.5 mol% Nd-PTR for the same transition is 90.3% and the induced emission cross section is 1.743 x 10(-20) cm(2). The saturation intensity for F-4(3/2 )-> I-4(11/2) laser transition in the same sample is 20.62 kW/cm(2), it is lower than that in some commercially produced glasses of same Nd3+-concentration. Laser action of a 0.5 mol% Nd-PTR was demonstrated, it was found that the round-trip loss of this gain medium is 0.34%, this value is quite low, and it is comparable to that in some commercially fabricated Nd-YAG crystals.