Mid-infrared femtosecond laser-induced damage in TeO2-BaF2-Y2O3 fluorotellurite glass

Fluorotellurite glasses based on TeO 2 -BaF 2 -Y 2 O 3 (TBY) with a broadband transmission window of 350–6000 nm, relatively low phonon energy, stable chemical and physical characteristics compared to fluoride glasses have been investigated to develop high-powered mid-infrared (MIR) fiber lasers. In this work, a series of xTeO 2 -(90-x)BaF 2 −10Y 2 O 3 (TBYx) (x = 60,65,70,75 mol%) fluorotellurite glasses were prepared with the conventional melting-quenching method in an argon glove box. Then, laser damage characteristics of glass samples under 3000 and 4000 nm MIR femtosecond laser with different pulses was compared and studied. The TBY60 glass has the highest damage threshold, which reaches 1.08 J/cm 2 and 0.852 J/cm 2 at 4000 nm and 3000 nm, respectively. The femtosecond laser-induced damage threshold (LIDT) of TBY glasses decreased from 1.08 to 0.782 J/cm 2 as TeO 2 content increased from 60 to 75 mol% at the wavelength of 4000 nm. In addition, the effect of pulse numbers is consistent with exponential defect accumulation model.