LAUSR

We describe the propagation of arbitrary amplitude ion acoustic waves with electron exchange-correlation effects for two-dimensional quantum plasmas by using the quantum hydrodynamic model. The evolution of nonlinear waves in such plasmas is described by deriving a pseudoenergy-balance like equation, involving a Sagdeev-type pseudopotential. The effects of the key plasma configuration parameters, viz., quantum diffraction, electron exchange-correlation, and the angle of propagation of the wave, on the periodic and solitonic characteristics are studied in detail by employing the concept of dynamical systems. Also, we extend our investigation by considering an external periodic perturbation in a modified pseudoforce model. It is found that the dynamics of nonlinear ion acoustic oscillations in quantum plasma support periodic and quasiperiodic behavior depending on the external pseudofrequency. The implications of our results may have relevance in various dense astrophysical environments as well as in laboratory plasmas.