Martini Enrica, Giusti Federico, Benini Alice, Maci Stefano
Department of Information Engineering and Mathematics, University of Siena, Siena, Italy.
Nanophotonics. 2023 May 8;12(14):2973-2985. doi: 10.1515/nanoph-2023-0076. eCollection 2023 Jul.
Anisotropic Self-Complementary Metasurfaces (SC-MTSs) are structures constituted by an alternation of complementary inductive and capacitive strips, which are "self-dual" according to Babinet's duality principle. They support the propagation of two orthogonally polarized surface-wave modes with the same phase velocity along the principal directions (i.e., along the strips and normal to them). The isofrequency dispersion curves of these modes are hyperbolas, and therefore, these MTSs fall in the category of hyperbolic MTSs. It is shown here that the hyperbolic dispersion curves may degenerate in same cases into almost straight lines, which implies that the velocity of energy transport is constantly directed along the same direction for any possible phasing orthogonal to the strips. In this circumstance, the SC-MTS can be conveniently used to design dual-polarized leaky-wave antennas by modulating the impedances of the complementary strips.
各向异性自互补超表面（SC-MTSs）是由互补电感和电容条交替构成的结构，根据巴比涅原理，它们是“自对偶”的。它们支持两种正交极化的表面波模式以相同相速度沿主方向（即沿条带方向及其法线方向）传播。这些模式的等频色散曲线是双曲线，因此，这些超表面属于双曲线型超表面。本文表明，在某些情况下，双曲线色散曲线可能退化为几乎是直线，这意味着对于与条带正交的任何可能相位，能量传输速度始终沿同一方向。在这种情况下，通过调制互补条带的阻抗，SC-MTS可方便地用于设计双极化漏波天线。
