Characterisation of bifurcation and chaos in silicon microring resonator

This study investigates the non-linear behaviours of light known as bifurcation and chaos during the propagation of light inside a non-linear silicon microring resonator (SMRR). The aim of the research is to use the non-linear behaviour of light to control the bifurcation and chaos of SMRR, which are used in engineering, biological and security systems. Bifurcation and chaos control deals with the modification of bifurcation characteristics of a parameterised non-linear system by a designed control input. The parameters of the SMRR cause bifurcation to happen in smaller round-trips among the total round-trip of 20 000 or input power. Effective parameters such as the refractive indices of a silicon waveguide, coupling coefficients (κ) and the radius of the ring (R) can be selected properly to control the non-linear behaviour. Simulated results show that rising non-linear refractive indices, coupling coefficients and radii of the SMRR lead to descending input power and round-trips when bifurcation occurs. Therefore bifurcation behaviour can be seen at a lower input power of 44 W, where the non-linear refractive index is n2=3.2×10−20 m2/W. The smallest round-trips of 4770 and 5720 can be seen for the R=40 µm and κ=0.1, respectively.