Plasmonic switching and bistability at telecom wavelength using the subwavelength nonlinear cavity coupled to a dielectric waveguide: A theoretical approach

Abstract

Theoretical investigation of optical switching in a plasmonic device comprising a metal-dielectric-metal waveguide perpendicularly coupled to a single nanocavity is reported. The cavity is filled with a third order nonlinear Kerr material whose optical properties are manipulated using a control beam to trigger the switching operation. The performance of the switch is quantitatively evaluated and compared with other switching mechanisms used in a similar plasmonic structure. The comparative study reveals that the efficiency of our plasmonic switch is many folds higher and hence advantageous over absorption switching. The dependence of switching efficiency on material parameters and input intensity of the control illumination is demonstrated in detail. Switching efficiency is calculated using various nonlinear crystals, glasses, liquids, and other materials. Bistability study and consequent determination of the hysteresis loop width provides an idea of required threshold intensity and sensitiveness of the nonlinear plasmonic switch.