用传统熔融法制备了一系列高重金属氧化物(Bi2O3)含量的Bi2O3-B2O3-SiO2三元系统玻璃. 用棱镜耦合仪测量了各个玻璃样品在632.8nm波长下的线性折射率n, 结果表明玻璃的n值在1.9~2.1范围内且随着Bi2O3含量的增加而增大, 其原因是由于Bi 3+离子具有高极化率; 用分光光度计测量了各个玻璃样品的线性吸收谱, 结果表明玻璃的带隙Eopg值在2.229～2.268eV之间,且随Bi2O3含量的增加而减小. 用开孔Z扫描实验测量了各个玻璃样品在770、800、 850nm三个波长下的非线性吸收系数β, 由于三个测量波长的光子能量hv（1.61, 1.55, 1.46eV）处于各个玻璃样品的带隙（Eopg）和半带隙（Eopg/2）之间, 表明实验中的非线性吸收属于双光子吸收（TPA）. 实验结果表明：在3个测量波长下, Bi2O3含量最小的样品由于能隙状态的作用而体现出谐振型的TPA, 其β值很高（(3.6~6.1)×10-12m/W）, 说明其能应用在光限幅器中. 另一方面, Bi2O3含量较高的样品只在770nm波长下才表现出微弱的非谐振类的TPA, 并且β值随着Bi2O3含量的增加而增大, 这表明它们在全光开光器（AOS）中有极高的应用潜力.
A serial of glass samples in Bi2O3-B2O3-SiO2 ternary system with high heavy metal oxide (Bi2O3) content were prepared by using conventional melting technique. Their linear refractive indexes n at 632.8nm were measured by prismcoupler, it showed that the n values were ranged from 1.9 to 2.1, and increased with increasing Bi2O3 content which was due to the high polarizability of Bi 3+ ions; their linear absorption spectra were depicted by spectrophotometer, and the optical band gaps Eopg were in the range from 2.229eV to 2.268eV while exhibited decreasing tendency with increasing Bi2O3 content. By employing open apertured Z-scan measurements at various wavelengths (770, 800, and 850nm), nonlinear absorption coefficients β which were due to twophoton absorption (TPA) since the incident photon energy hv (1.61, 1.55, and 1.46eV) of measured wavelengths were between Eopg/2 and Eopg of all samples studied were obtained. The results showed that the glass sample with lowest Bi2O3 content exhibited highest TPA coefficients ((3.6~6.1)×10 -12 m/W) which indicated as resonatetype induced by gap state at all measured wavelengths, demonstrating the sample can be applied in optical limiter. On the other hand, glass samples with higher Bi2O3 content showed offresonatetype TPA only at low wavelength of 770nm, and their TPA coefficients β increased with Bi2O3 content leading to the great potentials in all-optical switching (AOS).
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