Subwavelength-Scale 3D Broadband Unidirectional Waveguides Based on Surface Magnetoplasmons at Terahertz Frequencies

Unidirectional electromagnetic modes have significant potential for routing radiation and are highly desirable various applications, such as isolators, splitters, switches. In this study, we theoretically investigate surface magnetoplasmons (SMPs) in a four-layer structure consisting of perfect magnetic conductor (PMC)–semiconductor–dielectric–metal, which exhibits complete unidirectional propagation. We extend to 3D model by decreasing the width PMC-semiconductor part an appropriate value demonstrate that SMPs proposed waveguide retain Our findings indicate robust backscattering caused roughness defects. Moreover, can be efficiently coupled conventional microstrip line waveguides. results (based on numerical method) based semiconductors offer promising approach creating devices with new functionalities terahertz regime below diffraction limit.