In the theoretical part we briefly reviewed some basic definitions of deterministic chaos. We also reviewed the algorithm of constructing phase portrait, which is justified by embedding theorem using Lorentz attractor.
In the experimental part we studied the nonlinear response of Ammonium Sulfate [$(NH_4)_2SO_4$] to A.C. electric field. Stable period-2 bifurcation signal, which is a mechanical response of Ammonium Sulfate, was found near $T_c$. But only unstable signal was found far from $T_c$.