We demonstrate strong photonic thermal rectification effect between polar dielectrics plate and the composite metamaterials containing nonspherical polar dielectric nanoparticles with small volume fractions. Thermal rectification efficiency is found to be adjusted by the volume fractions and the nanoparticles' shape, and it can be as large as 80% when the polar dielectric nanoparticles are spherical in shape and are in the dilute limit with the volume fraction f = 0.01. Physically, there exists strong electromagnetic coupling between the surface phonon polariton mode of polar dielectrics plate and the localized surface phonon polariton mode around polar dielectric nanoparticles. The results provide alternative new freedom for regulating energy flow and heat rectification efficiency in the near field, and may be helpful for design of multiparameter adjustable thermal diodes.

我们展示了极性介电板与含有小体积分数的非球形极性介电纳米粒子的复合超材料之间的强光子热整流效应。发现热整流效率受体积分数和纳米粒子形状的影响，当极性介电纳米粒子呈球形并且在体积分数f的稀限内时，热整流效率可高达80%= 0.01。在物理上，极性介质板的表面声子极化模式与极性介质纳米粒子周围的局域表面声子极化模式之间存在强电磁耦合。该结果为近场调节能量流和热整流效率提供了替代的新自由度，并可能有助于多参数可调热二极管的设计。