Experimental observation of a torus-doubling transition to chaos near the ferroelectric phase transition of a KH2PO4 crystal

A ferroelectric KH2PO4 crystal is implemented in a simple series connection of an RLC circuit and the transition to chaos near the phase-transition te mperature is investigated. The torus-doubling scenario to chaos, the theory of which was expounded by Kaneko for high-dimensional dynamical systems, h as been found in the crystal. These experimental results suggest that obser vation of the nonlinear dynamical behavior in condensed matter can give muc h information about the correlation between the generation of nonlinearity and the order-parameter dynamics of the crystal near the phase-transition t emperature. [S1063-651X(99)01311-2].