Absorption spectra and Judd-Ofelt theory analysis of Er³⁺ doped borosilicate glass

Er³⁺-doped borosilicate glass samples doped with different concents of Er³⁺ are prepared by the technique of high-temperature melting. The optical density and absorption spectrum of this glass is measured and analyzed. Measured spectra-line strengths of the transition is compared with the calculated electric dipole spectra-line strengths by least-squares techniques, and the J-O intensity parameters Ω_λ(λ = 2,4,6) and oscillator strengths of Er³⁺ are calculated using Judd-Ofelt theory, and the root-mean-square deviation (δ) is calculated. The effects of the Er concentration on the above parameters are discussed. The result indicates when the Er³⁺ concentration is 21mol%, optical density at 0.53 μm (D_{0.53 μm}) is up to 4 and the value of Ω₂ is max. At the same time, the ambience of Er³⁺ in glass is changed, the symmetrical characteristic is decreased, and the covalent characteristic is increased.