Near-infrared emissions with widely different widths in two kinds of Er 3+-doped oxide glasses with high refractive indices and low phonon energies

Abstract

Er 3+-doped alkali–barium–bismuth–tellurite (LKBBT) and alkali–barium–bismuth–gallate (LKBBG) glasses with high refractive indices and low phonon energies have been designed, fabricated, characterized and compared. Intense 1.53 μm emissions with widely different widths in the two kinds of glasses were observed and recorded under 980 nm diode laser excitation. The full-widths at half-maximum of the 1.53 μm emission bands in LKBBT and LKBBG glasses are 58 and 40 nm, and the lifetimes of them were measured to be 3.21 and 3.97 ms, respectively. The quantum efficiencies for the 4I 13/2 level in both glasses are almost 100%. The 1.53 μm broad and narrow emissions with high spontaneous emission probabilities and large emission cross-sections indicate that Er 3+-doped LKBBT and LKBBG glasses are suitable materials in developing broadband optical amplifier and infrared laser, respectively.