GeO_2-Bi_2O_3-MO_x(MO_x=WO_3,BaO)玻璃近红外超宽带发光的研究

Study of near infrared emission property of GeO_2-Bi_2O_3-MO_x(MO_x=WO_3, BaO) glasses

用高温熔融法制备了(99.5-χ)GeO2-χBaO-0.5Bi2O3(χ=3,6,9mol%)与(99.5-φ)GeO2-φWO3-0.5Bi2O3(φ=3,6,9mol%)玻璃,测定了样品的发射光谱(800nmLD激发)、吸收光谱、荧光衰减和差热曲线.实验结果表明,在GeO2-WO3-Bi2O3系统玻璃中,随着WO3含量的增加,在1260nm处的发光强度增强,荧光半高宽(FWHM)增宽,荧光寿命增长,而且玻璃的吸收边带发生明显的红移;在GeO2-BaO-Bi2O3系统玻璃中,随着BaO含量的增加,玻璃在1290nm处发光强度增强,FWHM增宽,荧光寿命增长,吸收边带也有明显的红移.从吸收边带发生红移的情况,结合发射光谱和荧光衰减曲线特性,我们推断玻璃样品在近红外的宽带发光可能由Bi5+离子所引起.从荧光特性估算了玻璃的σp×τ和σp×Δλ值,这些玻璃均具有较小的σp×τ和较大的σp×Δλ特性,说明GeO2-Bi2O3-MOx(MOx=WO3,BaO)系统玻璃是研制成近红外(O到S波段)超宽带光纤放大器的良好材料.

Glasses with compositions （ 99.5-Χ） GeO2 - Χ BaO-0.5 Bi2 O3 （ Χ = 3, 6, 9 mol % ） and （99.5 - ψ） GeO2 - ψ WO3 -0.5 Bi2 O3 （ψ=3,6, 9 mol% ）were prepared by conventional melting method. Their emission spectra （using 800 nm LD excitation）, fluorescence decay curves, absorption spectra and DTA curves were measured. Concomitant with the increase of WO3 concentration in the glasses system GeO2-WO3-Bi2 O3, were the enhancement of glass thermal stability and emission intensity （centered at 1260 nm） as well as the increase of FWHM and lifetime, and along with the increase of BaO concentration in the glass system GeO2-BaO-Bi2 O3, were the enhancement of emission intensity （centered at 1290 nm）, the increase of FWHM and the prolongation of lifetime. In addition, in both groups, the absorption edges showed a red-shift with the increasing amount of WO3 or BaO, indicating that the Bi^5＋ ions may be responsible for the super broadband emission. In particular, the values of σp × τ and σp×Δλ, parameters deduced from the emission properties suggested that the prepared glasses are a kind of promising material for optical amplifier covering the O to S communication bands.