全光开关用过渡金属Fe、Co、Ni量子点玻璃的制备及三阶非线性光学性质的研究

By stabilizing the nanoparticles in the glass substrate, the problems of transition metal nanoparticles for being easily oxidized and aggregated can be solved effectively. Importantly, the nonlinear optical properties of the glass could be enhanced significantly by the magnetic Fe, Co, Ni nanoparticles. The ultrafast nonlinear optical response of the as-obtained glass could be produced under the operation of external magnetic field with low-energy laser, demonstrating the great potential applications in the all-optical switching. Therefore, the transition metal Fe, Co, Ni quantum dots glass with large third order nonlinearity will be prepared by the easy-operation and controllable sol-gel method. The microstructure and formation mechanism of these quantum dots in glass will be investigated in detail by adjusting the sizes of the nanoparticles, the doping patterns and the doping concentration. Meanwhile, the optimal parameters to combine the stability, optical properties, the response time, optical loss, and magnetic performance of the glass would be explored. The various factors which affect the third-order nonlinear optical property will be intensively discussed by the Z-scan technique, and then the third-order nonlinear mechanism of glass will be optimized. In addition, the figure of merit of quantum dots glass will also be investigated, and the relation of microstructure of transition metal quantum dots and third-order nonlinear optical properties of glass will be established. Further, it would be expected to provide the theoretical and technical support for the application in the all optical switching of the as-obtained transition metal Fe, Co, Ni quantum dots glass.

将过渡金属纳米晶稳定在玻璃基体中，不仅有效地解决了过渡金属纳米颗粒易氧化、易团聚等问题，且磁性Fe、Co、Ni纳米颗粒可显著提高玻璃的非线性光学性能。所得玻璃在外加磁场和低能量激光的作用下有望产生超快非线性光学响应，在全光开关等领域具有巨大的应用前景。因此，本项目拟采用可控易操作的溶胶-凝胶法制备具有大非线性的过渡金属Fe、Co、Ni量子点玻璃。通过调节纳米颗粒尺寸、掺杂方式、掺杂浓度等，对玻璃中量子点的微结构及形成机理进行研究，探讨该掺杂玻璃的稳定性、光学性能、响应时间、光学损耗、磁学性能等因素的最佳结合点。采用Z-scan 技术深入探讨该量子点玻璃的三阶非线性光学性能的影响因素，完善其三阶非线性效应的产生机理；研究该量子点玻璃的品质因子，建立含过渡金属量子点玻璃的微结构与三阶非线性光学特性的关系，为其在全光开关领域的应用提供理论和技术支持。

非线性光学材料因为在光电子技术和信息领域有很大的潜在应用价值，引起了广泛的关注。其中，金属纳米晶玻璃复合材料更成为了研究重点。目前的金属纳米晶玻璃在非线性领域方面的研究工作主要集中于贵金属纳米晶的研究，而对成本更低的过渡金属纳米晶玻璃却鲜少涉及。尤其是，将过渡金属纳米晶稳定在玻璃基体中，不仅有效地解决了过渡金属纳米晶易氧化、易团聚等问题，还可显著提高玻璃的非线性光学性能。因此，本项目采用溶胶-凝胶技术结合气氛热处理路线，制备了各种类型的含过渡金属（Ni, NiO, Cu3.8Ni, C0.81Ni0.19 , Fe2O3, Fe3O4和Co）纳米晶的钠硼硅玻璃。通过调节纳晶尺寸、掺杂方式、掺杂浓度等，对玻璃中纳米晶的微结构及形成机理了进行研究。通过Z-scan 技术深入探讨该类量子点玻璃的三阶非线性光学性能的影响因素，建立含过渡金属量子点玻璃的微结构与三阶非线性光学特性的关系，为其在全光开关领域的应用提供理论和技术支持。