新型高受激布里渊特性的硫系玻璃光纤研究

Chalcogenide Glass (ChG) fibers have excellent infrared transmission performance and extremely high optical non-linear coefficients. Their Stimulated Brillouin scattering (SBS) gain coefficients are two orders of magnitude greater than those of silica fibers. Therefore, the development of ChG optical devices based on strong SBS effect has attracted extensive attention in many applications including low threshold Brillouin fiber lasers, slow light generation and microwave photonic filters. However, there are still deficiencies in the study of the SBS effect in ChG fibers, such as the design and regulation of the glass composition, the interaction mechanism of optical and acoustic waves in the SBS nonlinear process, and the low-loss coupling between ChG and silica fibers. This proposal intends to investigate host material composition and performance regulation of strong SBS effect in novel ChG fibers and design fiber structures to enable effective couplings between the optical and acoustic fields. The SBS gain model of ChG fibers with different materials and fiber structures will be improved theoretically and novel ChG fibers with large SBS gain will be developed experimentally. Meanwhile, this proposal also intends to achieve low-loss fusions between ChG and silica fibers. Low threshold SBS fiber lasers based on ChG fibers will be realized as final products of this project. The implementation of this project can provide a foundational scientific basis to the development of novel SBS effect-based CHG photonics devices that have independent intellectual property rights.

硫系玻璃光纤具有优良的红外透过特性和极高的非线性系数，其受激布里渊散射（SBS）增益系数高出石英材料2个数量级。因此，基于高SBS特性硫系光纤在低阈值布里渊光纤激光器、慢光产生、微波光子滤波器等领域在国际上引起广泛关注。但在硫系光纤基质材料组成与高SBS效应调控，硫系光纤中SBS非线性过程中光场与声场相互作用耦合机理、硫系光纤低损耗耦合等基础方面存在不足，本课题拟通过阐明新型高SBS效应硫系玻璃光纤的基质材料组成与性能调控方法、声场与光场有效耦合的光纤结构设计，优化不同材质和光纤结构的硫系光纤SBS增益特性理论模型，研制出高SBS效应的新型硫系玻璃光纤，解决硫系玻璃光纤与石英光纤低损耗熔接技术，实现较低阈值功率SBS光纤激光输出。本项目的实施可为今后推动具有自主知识产权的基于高SBS效应硫系玻璃材料的新型光子器件发展提供科学依据。

硫系玻璃光纤具有超宽的红外透过范围和极高的非线性系数。近年来，得益于高受激布里渊（SBS）增益系数，硫系光纤在低阈值布里渊光纤激光器 、微波光子滤波器等研究领域引起国际上的广泛关注。本项目开展了新型高SBS效应硫系玻璃光纤的基质材料组成与性能调控方法、声场与光场有效耦合的光纤结构设计、新型硫系玻璃光纤制备和异质光纤低 损耗熔接技术等研究工作。.项目取得的重要研究结果包括：(1)探明了Ge-As-S、Ge–Sb–S、Ge-Te-AgI、Ge-As-Se-Te等具有优良声光效应的硫系玻璃的声光特性与组成内在变化规律，优化出多组高布里渊增益系数gB的组成；（2）设计了一种基于高gB值Ge-As-Se-Te玻璃作为纤芯玻璃的2 μm工作波长布里渊增益光纤；（3）提出了利用模场适配器可以有效降低小纤芯硫系光纤与石英光纤耦合损耗（<1dB）和腔损耗方法，且实现了氟碲酸盐光纤和硫系光纤之间熔接损耗值为0.503dB；（4）搭建了基于硫系光纤的环形腔布里渊激光器装置，通过对激光腔腔长和损耗的理论优化，实现了2 μm波段的低阈值、亚kHz线宽的硫系光纤布里渊激光输出。.项目执行期间在Journal of Lightwave Technology.、Opt. Express等期刊共发表27篇学术论文（其中：SCI论文21篇，EI论文3篇）；制定获批国家标准3项，申请发明专利6项，其中授权专利1项、；参编Springer出版社专著1部；培养毕业研究生3名。承办3次学术研讨会，14人次参加国内外学术会议并作报告。本项目成果为今后推动自主知识产权的新型红外布里渊光纤及器件发展提供了科学依据。