## Differential and Integral Equations

### Existence of a periodic solution in a Chua's circuit with smooth nonlinearity

Fu Zhang

#### Abstract

In this paper, we consider Chua's circuit: $$\varepsilon u'=z+f(u) , \ \ z'=u+w-z, \ \ w'=-\beta z-\gamma w,$$ where $f(u)$ is chosen as a cubic function, $\beta>0$ and $\gamma\geqslant 0$ are constants, and $\varepsilon>0$ is a small parameter. We prove that the flow defines a Poincar$\acute{e}$ map from a compact set which is homeomorphic to the unit disk to itself and then apply Brouwer's fixed-point theorem to conclude that the system has a big'' periodic solution. This global analysis is viewed as a step towards understanding chaos in this model analytically.

#### Article information

Source
Differential Integral Equations, Volume 18, Number 1 (2005), 83-120.

Dates
First available in Project Euclid: 21 December 2012