Topological Plasmonic Ring Resonator

Topological plasmonic provides a new insight for the manipulation of light. Analogous to exotic nature of topological edge states in topological photonics, topological plasmonic combines concepts from topology and plasmonics. By utilizing topological protection, plasmons can be made to propagate without significant scattering or decay, even in the presence of defects or disorder. Herein, we present a study on the design, characterization, and manipulation of topological plasmonic chains of discs based on the Su-Schrieffer-Heeger model made into a ring resonator. The investigation focuses on exploring the unique properties of these resonators and their potential to support topologically protected edge modes, within the continuum of rotationally symmetric optical modes of a ring. To observe the topological edge modes in rotationally symmetric chains, we employ a symmetry-breaking excitation technique based on electron beams. It analyzes the influence of parameters such as dimerization and loop numbers on the presence of topological modes. Additionally, we explore the manipulation of electron impact positions to control the direction of propagation and selectively excite specific bulk or edge modes. The findings contribute to a deeper understanding of topological effects by numerically investigating their design principles and exploring techniques to manipulate topological edge modes. The insights gained from this study have implications for the development of nanoscale plasmonic systems with customized functionalities, potentially impacting areas such as nanophotonics and quantum information processing.