Electromagnetic modelling of near-field plasmonic switches based on fractal nanoantennas

Abstract

We propose plasmonic switches based on nanoantennas with fractal features on top of vanadium dioxide (VO2) thin films. These plasmonic switches can be devised by utilizing various kinds of fractals like – the Sierpenski fractal or the Koch fractal. When exposed to heat, voltage, or infrared radiation, the VO2 thin film undergoes a phase transition from its insulator state to its metal state, thus leading to switching in the total optical behavior of the proposed switch. In this paper, the switching performance characteristics of the near-field plasmonic switches (NFPS) are numerically analyzed. As the iterations of the fractal features of the switch are increased, the electric-field intensity is enhanced during ON state of the NFPS and the electric-field intensity is reduced during OFF state of the NFPS. We also employ Finite Difference Time Domain (FDTD) analysis to numerically analyze the VO2 layer thickness effect on the performance of the NFPS. These plasmonic switches possess the potential to be used as elementary switching devices in computing networks and optical communication networks.