Ga_(2)S_(3)-Sb_(2)S_(3)-Ag_(2)S硫系玻璃和光纤的制备及性能研究

Preparation and properties of Ga_(2)S_(3)-Sb_(2)S_(3)-Ag_(2)S chalcogenide glasses and fibers

本工作确定了一种新型的Ga_(2)S_(3)-Sb_(2)S_(3)-Ag_(2)S硫系玻璃体系的玻璃形成区,研究了玻璃的热稳定性和光学性能、稀土离子掺杂玻璃的中红外发光特性以及玻璃的成纤性能,评估了该玻璃在中红外波段的应用潜力.实验结果表明,Ga_(2)S_(3)-Sb_(2)S_(3)-Ag_(2)S体系的玻璃形成区为~10%—30%Ga_(2)S_(3),~60%—80%Sb_(2)S_(3)和~0—15%Ag_(2)S(均为摩尔分数);该玻璃具有较宽的红外透过范围(~0.8—13.5μm)、较高的线性折射率(~2.564—2.713@10μm)和较大的三阶非线性折射率(~9.7×10^(-14)—15.7×10^(-14)cm^(2)/W@1.55μm);使用1.32μm激光抽运,稀土离子Dy^(3+)在该玻璃中表现出较强的2.91μm和4.41μm中红外发射,发射量子效率分别达76.6%和70.8%;拉制的20Ga_(2)S_(3)-75Sb_(2)S_(3)-5Ag_(2)S:Dy^(3+)(质量分数为0.05%)/20Ga_(2)S_(3)-70Sb_(2)S_(3)-10Ag_(2)S (纤芯/包层)光纤在2—8μm具有良好的传输性能,最低损耗为~3.5 dB/m (@5.7μm).这些优异的性能使得该玻璃或光纤有望应用于红外热成像、非线性光学、中红外光纤激光器等领域.

With the rapid development of infrared technology and the wide applications of infrared optical components,the demand for infrared optical materials has risen significantly.Chalcogenide glass has been considered as one of the most popular infrared optical materials because of its wide infrared transmission range,high refractive index,low phonon energy,good rheological properties,low cost,etc.In this work,a new type of Ga_(2)S_(3)-Sb_(2)S_(3)-Ag_(2)S chalcogenide glass system is reported,and its glass forming domain is determined.The thermal stability and optical property,mid-infrared(MIR) emission of rare earth dopant,and fiber-forming property for the glasses are studied.The potential applications of the glasses in the MIR region are also evaluated.The experimental results show that the Ga_(2)S_(3)-Sb_(2)S_(3)-Ag_(2)S system has a glass forming domain of~10%-30% Ga_(2)S_(3),~60%-80% Sb_(2)S_(3)and~0-15% Ag_(2)S(all in molar percentage).These glasses have a wide infrared transmission range of~0.8-13.5μm,relatively high linear refractive indices of~2.564-2.713(at 10 μm),and relatviely large third-order nonlinear refractive indices of~9.7×10^(-14)-15.7×10^(-14)cm^(2)/W(at 1.55μm).These excellent properties make the Ga_(2)S_(3)-Sb_(2)S_(3)-Ag_(2)S glass promising material in the fields of infrared thermal imaging and nonlinear optics.Under the excitation of 1.32 μm laser,the rare earth dopant Dy^(3+)shows strong2.91 μm and 4.41 μm MIR emissions in the glass.According to the J-O theory,the three strength parameters(Ω2,Ω4,Ω6) of Dy^(3+)in 0.05% weight of Dy^(3+)doped 20Ga_(2)S_(3)-75Sb_(2)S_(3)-5Ag_(2)S glass are 7.38×10^(-2)0cm^(2),2.24×10^(-2)0cm^(2) and 0.75×10^(-2)0cm^(2),respectively.The quantum efficiencies of the 2.91 μm and 4.41 μm emissions are calculated to be 76.6% and 70.8%,respectively,while the stimulated emission cross sections of those two bands are 1.27×10^(-2)0cm^(2) and 1.43×10^(-2)0cm^(2),respectively.The fiber based on 20Ga_(2)S_(3)-75Sb_(2)S_(3)-5Ag_(2)S:0.05% Dy^(3+)core glass and 20Ga_(2)S_(3)-70Sb_(2)S_(3)-10Ag_(2)S cladding glass is fabricated by rod tube method.The fiber has good transmission performance in the 2-8μm wavelength range,and the minimum loss is~3.5 dB/m at 5.7μm.The Dy^(3+)ions show intense 2.93μm and 4.45μm MIR emissions in the fibers under 1.32μm excitation.These results indicate that the Dy^(3+)doped Ga_(2)S_(3)-Sb_(2)S_(3)-Ag_(2)S glass fiber can be a promising candidate for MIR fiber laser medium.