Dynamic control of electromagnetic wave propagation with the equivalent principle inspired tunable metasurface

TLDR

Transmission and reflection are fundamental properties of electromagnetic wave propagation through obstacles, and independent control of their magnitude and phase is essential for free manipulation of EM waves. The study employs the equivalent principle to determine the surface electric and magnetic impedances needed for a passive metasurface to achieve arbitrary transmission or reflection magnitude and phase. A tunable metasurface is designed based on the derived impedance relations, enabling independent tuning of transmission and reflection characteristics. The metasurface achieves full 360° phase tuning at unity transmissivity, allows transmissivity to vary from 0 to 1 while maintaining near‑zero phase, and similarly tunes reflection magnitude and phase, offering potential for dynamic EM beam forming and scanning.

Abstract

Transmission and reflection are two fundamental properties of the electromagnetic wave propagation through obstacles. Full control of both the magnitude and phase of the transmission and reflection independently are important issue for free manipulation of electromagnetic wave propagation. Here we employed the equivalent principle, one fundamental theorem of electromagnetics, to analyze the required surface electric and magnetic impedances of a passive metasurface to produce either arbitrary transmission magnitude and phase or arbitrary reflection magnitude and phase. Based on the analysis, a tunable metasurface is proposed. It is shown that the transmission phase can be tuned by 360° with the unity transmissivity or the transmissivity can be tuned from 0 to 1 while the transmission phase is kept around 0°. The reflection magnitude and phase can also been tuned similarly with the proposed metasurface. The proposed design may have many potential applications, such as the dynamic EM beam forming and scanning.