零折射率材料的物理与应用

零折射率材料因其异常的电磁/光学特性在电磁波操控、新型天线和波导器件、非线性光学、光学吸收、电光调制等领域有着广泛的应用前景。文章首先介绍了零折射率材料的分类和实现方法，然后总结了零折射率材料的基本概念和电磁/光学特性，包括电磁波在零折射率材料中的折射、反射特性和“隧穿”效应，掺杂杂质对二维和三维体系的零折射率材料的影响，各向异性零折射率的电磁特性，零折射率材料内外的电场分布特性；最后介绍了零折射率材料的部分典型应用，并对零折射率材料的研究进行了展望。

The physics and applications of zero-index materials

Due to their extraordinary electromagnetic/optical properties, zero-index media have extensive application prospects in the manipulation of electromagnetic waves, novel antenna and waveguide devices, nonlinear optics, optical absorption, electro-optical modulation, etc. In this review, we first present the classification and realization of zero-index materials. Then, we focus on their fundamental concepts and electromagnetic/optical properties, including refraction, reflection and tunneling effects of electromagnetic waves, the influence of doped defects in both two- and three-dimensions, features of anisotropic zero-index media, and the distribution of electric fields in and outside the medium. Finally, we review a variety of applications, and provide a brief summary and outlook on future studies of these materials.