An all-optical 1× 2 Demultiplexer Using Kerr Nonlinear Nano-plasmonic Switches

Abstract

In this paper, a novel surface plasmon polariton (SPP) based all-optical 1× 2 demultiplexer, which is based on a modified Y-branch structure and a controllable switching module, is presented. In the modified Y-branch structure, which acts as an ideal wide-band splitter, the width of the branches are chosen as one half the input waveguide. The switching module is constructed using two nano-plasmonic racetrack-shaped disk resonators which are side coupled to the branches of the Y-branch structure. It has been shown that using a pump light power, the transmissions of the input signal into the output ports can be controlled. The simulation results are based on the two dimensional finite-difference time-domain (2D FDTD) method. In the proposed device, the “on” state transmission coefficients and the extinction ratios (measured at the output ports), for the pump light source with the wavelength of 660 nm and the intensity of 1.75 MW/cm2, are about 0.74 and 28.75 dB, respectively. Furthermore, in this case, the switching times of the proposed device, measured at the port 1 and port 2, are about 100 fs and 180 fs, respectively. It is expected that the proposed device can find applications in all-optical signal processing.