Simulations of multi-functional optical devices based on a sharp 90° bending graphene parallel pair

Abstract

We theoretically demonstrate the properties of surface plasmon polaritons (SPPs) propagating along a 90° sharp bending graphene parallel pair and the mode conversion phenomenon around the corner. They are illustrated numerically using the finite-difference time-domain (FDTD) method. As applications, a couple of bending graphene sheets are employed to construct Mach–Zehnder interferometers, T-shaped splitters and switches, and two-Y-shaped splitters and switches. By means of a gate voltage, these devices present novel optical properties and yield a new way to obtain tightly confined and low loss SPPs for nanophotonic networks. Undoubtedly, the proposed devices will have significant application prospects in ultra-compact integrated circuits for optical communications and switching.