NONLINEAR-INTERACTION OF TRANSVERSE ACOUSTICAL AND OPTICAL WAVES IN MICROPOLAR ELASTIC MEDIA

In this study nonlinear interaction between modulated transverse waves in a weakly nonlinear micropolar elastic medium is considered. The in teraction is assumed to be between transverse acoustical and optical p lane waves with equal group velocity. By using the reductive perturbat ion method, it is shown that the slow modulation of the complex envelo pes is described by four coupled nonlinear evolution equations. As a s pecial case. these equations reduce to a system of four coupled nonlin ear Schrodinger equations. Some special solutions of the evolution equ ations, namely, nonlinear plane wave and envelope solitary wave soluti ons, are also presented.