Chaos in a Chua system with order less than two

The conventional understanding of order holds that the order of a system is the degree of its highest order derivative. This paper presents a system whose order is less than two which exhibits chaotic characteristics. Specifically, a fractional-order Chua system of order 1.9 is shown to undergo period doubling bifurcation and eventually displays a double scroll attractor. The chaotic behavior is predicted theoretically, and then demonstrated through simulation.