磁光材料的近场辐射传热增强及调控研究

Enhancement and modulation of near-field radiative heat transfer (NFRHT), are essential for high-efficiency energy utilization and thermal management in micro/nano scale. Magneto-optical materials can support magnetic-induced hyperbolic modes, surface polaritons and magneto-optical effect, which facilitate the enhancement and modulation of NFRHT. The project takes advantage of the scattering matrix method to study electromagnetic wave propagation properties of magneto-optical media, and considers the magneto-optical composite structures composed of magneto-optical media with nanomaterials, including grating, graphene and periodic pore arrays and so on. The magnetic-induced hyperbolic modes and the change of dispersion relation of surface polaritons brought by the magnetic field will be discussed. The magneto-optical effects in near-field two-body and three-body systems will also be studied. Then, on the basis of the fluctuation dissipation theorem, the project will analyze the effects of the coupled transfer modes in magneto-optical media and magneto-optical composite structures on NFRHT. Also, the mechanisms of modulation of NFRHT by magneto-optical effects will also be discussed. The project will carry out the NFRHT experiment under magnetic field in a near-field two-body system to demonstrate the analysis results. Expected research results are beneficial to high-efficiency energy utilization in micro/nano scale, and facilitate the thermal management for micro/nano electronic devices.

近场辐射传热的增强以及调控研究，对微纳尺度的高效能源利用和热管理至关重要。磁光材料可以支持磁致双曲线模式、表面极化激元以及磁光效应，这为增强及调控近场辐射传热提供便利。项目利用散射矩阵法研究磁光介质的电磁波传输特性，并同时考虑磁光介质与光栅、石墨烯和周期性孔阵列等纳米材料组成的磁光复合结构，分析磁致双曲线模式以及表面极化激元色散关系随磁场的变化，研究近场两体和三体系统的磁光效应；然后基于涨落耗散理论，分析磁光介质和磁光复合结构的耦合传输模式对近场辐射传热的影响，探讨磁光效应对近场辐射传热的调控机理。另外，在近场两体系统中，开展磁场影响下磁光材料的近场辐射实验，为以上理论分析提供实验验证。预期研究成果将有助于微纳尺度下的能量利用，并对微纳电子器件的热管理提供新的可行方案。

磁光材料的近场辐射传热研究，无论是对于高效能源利用和热管理，还是对于微纳尺度辐射传热物理内涵的深入理解，都有非常重要的意义。本项目首先基于散射矩阵理论和严格耦合波分析法，利用python语言构建了并行计算平台用于计算垂直磁场存在时的近场辐射传热；然后，基于此算法，针对多层结构的磁光双曲线材料，研究了磁场对其近场光子传输模式的影响机制，探讨了表面等离子体极化激元、双曲线模式以及偏振转换与磁场的依赖关系，并基于此实现对近场辐射传热的增强和调控；最后，搭建了近场辐射实验台架，深入研究了确定二维材料间距的反演方法，并开展了间距约为400 nm的石墨烯/六方氮化硼多层结构之间的近场辐射实验，发现了超过黑体极限3倍和6倍的传热增强。研究成果将有助于理解和验证磁光材料间的近场辐射传热机制，也为微纳电子器件的高效热管理提供可行方案。