Complex periodic structures in bi-dimensional bifurcation diagrams of a RLC circuit model with a nonlinear NDC device

We report the existence of complex periodic structures, forming intricate periodic networks, embedded in chaotic regions of bi-dimensional bifurcation diagrams (parameter spaces) of a chaotic circuit model. Such circuit is composed by a negative differential conductivity (NDC) device coupled with a three variable RLC tank circuit. Particularly, we focused on a semi-insulating Gallium Arsenide (GaAs) model of nonlinear NDC device which is capable of oscillating at low frequencies. We show the presence of many types of orbits regarding their topological structures, indicating that there are topological transitions in the parameter space.