Intense near-infrared emission of 1.23 μm in erbium-doped low-phonon-energy fluorotellurite glass

NIR emission studies and dielectric properties of Er(3+)-doped multicomponent tellurite glasses

Multicomponent tellurite glasses containing altered concentrations of Er2O3 (ranging from 0 to 1 mol%) were prepared by the standard melt quenching technique. Investigations through energy dispersive X-ray spectroscopy (EDS), Raman scattering spectroscopy, Fourier transform infrared (FTIR) spectroscopy, near-infrared (NIR) emission studies and dielectric measurement techniques were done to probe their compositional, structural, spectroscopic and dielectric characteristics. The broad emission together with the high values of the effective linewidth (~63 nm), stimulated emission cross-section (9.67 × 10(-21) cm(2)) and lifetime (2.56 ms) of (4)I13/2 level for 0.5 mol% of Er(3+) makes these glasses attractive for broadband amplifiers. From the measured capacitance and dissipation factor, the relative permittivity, dielectric loss and the conductivity were computed; which furnish the dielectric nature of the multicomponent tellurite glasses that depend on the applied frequency. Assuming the ideal Debye behavior as substantiated by Cole-Cole plot, an examination of the real and imaginary parts of impedance was performed. The power-law and Cole-Cole parameters were resolved for all the glass samples. From the assessment of the emission analysis and dielectric properties of the glass samples, it was obvious that the Er(3+) ion concentration had played a vital role in tuning the optical and dielectric properties and the 0.5 mol% of Er(3+) -doped glass was confirmed as the optimum composition.

Investigation of mid-infrared emission characteristics and energy transfer dynamics in Er(3+) doped oxyfluoride tellurite glass

Er(3+) doped oxyfluoride tellurite glasses have been prepared. Three Judd-Ofelt parameters Ωt (t=2, 4, 6) and radiative properties are calculated for prepared glasses. Emission characteristics are analyzed and it is found that prepared glasses possess larger calculated predicted spontaneous transition probability (39.97 s(-1)), emission cross section σem (10.18 × 10(-21)cm(2)) and σem × Δλeff (945.32 × 10(-28)cm(3)), corresponding to the 2.7 μm emission of Er(3+): (4)I11/2→ (4)I13/2 transition. The results suggest that the prepared glasses might be appropriate optical material for mid-infrared laser application. Moreover, rate equation analysis which is rarely used in bulk glass has been carried out to explain the relationship between emission intensity and Er(3+) concentration. The calculation results show that with the increment of Er(3+) concentration, the energy transfer up-conversion rate of (4)I13/2 state increases while the rate of (4)I11/2 state reduces, resulting in the change of 2.7 μm emission.