基于稀土掺杂纳米晶铁氧体的可调超表面器件研究

微波器件的多频带和频带可调谐技术已经成为当前通信技术领域的研究热点。但是，这些器件面临着结构复杂、损耗高等问题。本项目旨在利用溶胶凝胶法制备稀土掺杂纳米晶钇铁石榴石（YIG）铁氧体，通过掺杂不同成分和比例的稀土离子，研究稀土掺杂对纳米晶YIG晶体结构的影响规律，进而探索出晶体结构与饱和磁化强度、共振线宽、密度、电阻率等旋磁性能参数的相互关系；基于铁磁共振原理及以上结论，设计出一系列基于稀土掺杂纳米晶YIG铁氧体的磁可调超表面微波器件，明确纳米晶YIG超表面器件的电磁性能随饱和磁化强度、共振线宽等旋磁性能参数和相关晶体结构的变化规律，并建立对应关系体系；探索出通过调节纳米晶YIG旋磁参数提高超表面器件性能、简化结构的途径，发展出一系列低损耗、多个工作频带的纳米晶YIG磁可调超表面微波器件，为新型微波器件的研究开辟新的方向。

Microwave devices with multiband and tunable property have attracted great attentions in the field of microwave communication technology. However, such devices face limitations of complicated structure and high loss. In this project, the rare-earth ions doped nanocrystalline yttrium iron garnet (YIG) will be prepared by using the flux method. The effect of rare-earth ions doping technology on crystal structure of the nanocrystalline YIG will be investigated. And the dependence of gyromagnetic parameters such as saturation magnetization, ferromagnetic resonance line width on the crystal structure will be studied. According to the above results and ferromagnetic resonance theory, a series of magnetically tunable metasurface devices based on rare-earth ions doped nanocrystalline YIG will be designed. The electromagnetic behaviors of these devices dependence on gyromagnetic parameters and crystal structure will be investigated. Finally, magnetically tunable metasurface devices with low lossess and multiband will be explored by controlling the gyromagnetic properties of the rare-earth ions doped nanocrystalline YIG. This project offers new directions for the design of microwave communication devices.