A comprehensive review on hybrid plasmonic waveguides: Structures, applications, challenges, and future perspectives

This article offers an in-depth overview of hybrid plasmonic waveguides (HPWs), a burgeoning area poised to transform optical communication, data processing, biosensing, and nanophotonics. HPWs address the inherent trade-off between propagation loss and confinement by merging dielectric and plasmonic waveguide advantages, enabling nanoscale light confinement beyond the diffraction limit. The review begins with a foundational look at plasmonics, covering the theoretical underpinnings and history of HPWs, followed by a detailed analysis of various HPW structures like dielectric-loaded, metal-dielectric-metal, and metal-insulator-metal waveguides. It examines their unique benefits, fabrication complexities, and limitations, offering a comprehensive perspective on their performance. The article also surveys the significant applications of HPWs and their impact on different fields, and discusses the fabrication, measurement challenges, and material constraints. Highlighting areas needing further exploration, the conclusion points toward future advancements aimed at expanding HPW applications. This review aims to ignite further innovation in the promising area of plasmonics.