Exploring the optical properties of the 1.53 μ m emission in Er 3+-doped glass, anti-glass and ceramic in TeO2- Ta2 O5 - Bi2 O3 system

A series of 80TeO2 - 10Ta2O5 - 10Bi2O3 glasses, anti-glasses and ceramics doped with different concentrations of Er2O3, ranging from 0.25 % to 2 % mol, were synthesized to explore their structural transformation and optical properties. The maximum solubility of Er2O3 was identified at 1.25 % mol, beyond which the glass transitioned from an amorphous to a crystalline structure. The anti-glasses and ceramics obtained from the heat treatment of the parent glasses were also studied to gain insights into their optical properties. This study reveals a direct relationship between Er3+ ions concentration and full width at half maximum (FWHM) of photoluminescence spectra. The increase in Er3+ ions concentration correlates with a rise in FWHM, indicative of spectral broadening. Anti-glass exhibits a higher emission intensity, followed by ceramic and then glass, reflecting their distinct structural properties. Anti-glass doped with 1 % mol Er2O3 shows an FWHM over 130 nm under 578 mW pumping. The lifetime of the excited state 4I13/2 increases with the Er2O3 content in the anti-glass and the ceramic, with a notable decrease at 1 % mol Er2O3 ions for both materials, while in glass, the decrease is observed at 0.5 %. Emission cross-sections decrease with increasing Er3+ ions concentration and power, influenced by factors like thermal effects and saturation. The Judd-Ofelt theory highlights structural differences, with glasses having a more disordered structure and with an increase in the Omega 6 parameter across all materials, implying enhanced electric dipole line strength and spontaneous emission probability with higher Er2O3 content. Overall, this comprehensive study provides valuable insights into the optical behavior of Er3+ ions in these materials, essential for applications in laser design and optical amplifiers.