Realizable Leaky Wave Antenna Based on Spin Photonic Topological Insulators

The discovery of topological insulators and their photonic counterparts has led to significant advancements in electromagnetics. These materials offer an innovative way to control electromagnetic fields at the interface of trivial and topological materials. One exciting development in this field is the creation of topological metasurfaces that use propagating line waves as the edge mode, allowing for the introduction of topological transmission lines. The main focus of this study is to utilize a spin photonic topological insulator structure that has been designed using 30-degree rhombic cells to develop a leaky wave antenna application. Along with validating the topological behavior of the unit cell, we have also examined the angle of connection between the proposed topological and classical lines to optimize the transmission. This article presents a low-profile leaky wave antenna with one beam at either side, which is completely realizable because of the proportional pattern and little coupling between radiating elements. Moreover, the proposed antenna is a uniform left-handed leaky wave antenna that operates in the frequency range of 17.5-20 GHz, which is in the fast wave region. As a result, it achieves a directivity of 19.57 dB at 18.5 GHz with a 22.5-degree wide beam scan.