Active Nanophotonic Circuitry Based on Dielectric‐loaded Plasmonic Waveguides

Surface plasmon polaritons provide a unique opportunity to localize and guide optical signals on deeply subwavelength scales and can be used as a prospective information carrier in highly integrated photonic circuits. Dielectric‐loaded surface plasmon polariton waveguides present a particular interest for applications offering a unique platform for the realization of integrated active functionalities. This includes active control of plasmonic propagation using thermo‐optic, electro‐optic, and all‐optical switching as well as compensation of propagation losses. In this review, the principles and performance of such waveguides are discussed and the current status of the related active plasmonic components which can be integrated in silicon or other nanophotonic circuitries is summarized. A comparison of dielectric‐loaded and other plasmonic waveguides is presented and various material platforms and design pathways are discussed.