Preparation and Optical Properties of Er~(3+) -Doped Gadolinium Borosilicate Glasses

摘要

Er~(3+) -doped Gd_2O_3 -SiO_2-B_2O_3 -Na_2O glasses were prepared, and formation range of glass of Gd_2 O_3-SiO_2-B_2O_3 system was experimentally obtained. It is found that the glass phase can be formed only when the content of SiO_2 is 0～50% (molar fraction), Gd_2O_3 is 0～30% (molar fraction) and B_2O_3 is above 20% (molar fraction) in this glass system. The glass can also be obtained but becomes translucent at the contents of 60% (molar fraction) SiO_2 and 30% Gd_2O_3, or at the contents of 60% (molar fraction) SiO_2 and 30% (molar fraction) B_2O_3. There is no glass phase formed in other glass components. Glass forming ability for Gd_2O_3 content of 10% , was characterized by the value of β, the parameter of crystallization tendency, which is 0.32 ～ 1.76, obtained from the differential thermal analysis. The absorption and emission cross section, the J-O parameters Ωt_(2,4,6) and radiative transition probabilities were calculated by using the theory of McCumber and Judd-Ofelt. The emission properties at 1.5 μm of the samples are discussed with the product of full width at half maximum and stimulated emission cross section. It can be seen that the value of the FWHM x σ_e~(peak) product in the prepared glass is more than those of germanate, silicate and phosphate glasses. Furthermore , the maximum value of the product among these glasses reported in this work is close to that of oxyfluoride silicate glass. Therefore, the Er~(3+)-doped gadolinium borosilicate glass in this paper is a candidate for broadband erbium doped fiber amplifiers.