论文标题
基于本地Fabry-Perot共振的相梯度元信息
Phase-gradient metasurfaces based on local Fabry-Perot resonances
论文作者
论文摘要
在这项工作中，我们提出了一种新的机制，用于设计相位梯度元面（PGMS），以控制具有高效率的电磁波前。具体而言，我们设计了一个传输型PGM，该传输型PGM由周期性亚波长的金属狭缝阵列形成，充满了不同高度的相同介电阵列。据发现，当Fabry-Perot（FP）共振发生在介电区域内，除了完全传输的常见现象之外，两个相邻缝隙之间的传输相位差异完全相同，是一个非零常数。这些局部FP共振确保了可以完全覆盖0到2PI范围的超级电池的总相移，从而满足了PGM的设计要求。更多的研究表明，由于局部FP共振，相位差和填充介电的介电常数之间存在一对一的对应关系。类似的方法可以扩展到反射型案例和其他波前转换，从而为波浪操作创造了新的机会。
In this work we present a new mechanism for designing phase-gradient metasurfaces (PGMs) to control an electromagnetic wavefront with high efficiency. Specifically, we design a transmission-type PGM formed by a periodic subwavelength metallic slit array filled with identical dielectrics of different heights. It is found that when Fabry-Perot (FP) resonances occur locally inside the dielectric regions, in addition to the common phenomenon of complete transmission, the transmitted phase differences between two adjacent slits are exactly the same, being a non-zero constant. These local FP resonances ensure total phase shift across a supercell that can fully cover the range of 0 to 2Pi, satisfying the design requirements of PGMs. More studies reveal that due to local FP resonances, there is a one-to-one correspondence between the phase difference and the permittivity of the filled dielectric. A similar approach can be extended to the reflection-type case and other wavefront transformation, creating new opportunities for wave manipulation.
