Influence of amplitude-modulated excitation on the dynamic behaviour of polarisation of a material

This work concerns the modelling of the dynamics of polarisation of a centrosymmetric material subjected to an amplitude-modulated excitation (AME). The dynamic equation obtained for the polarisation is the Duffing equation with nonlinearities of orders 3 and 5. With the multiple scale method, the nonlinear resonances are studied. Periodic, multiperiodic, quasiperiodic and chaotic behaviour have been checked using the bifurcation diagram, Lyapunov exponent, phase space, Poincaré section and vibrational resonance using the fourth-order Runge–Kutta integration algorithm. The effects of various parameters of polarisation are analysed and very interesting results are obtained. The results obtained by the analytical methods are validated and complemented by the numerical simulations.