Opticalmechanical coupled SBS equations

A new type coulpled wave equations, whose acoustic branch is rewritten in terms of displacement, is established to describe SBS process. One dimensional backward SBS is researched by solving this coupled wave equations numerically and displacement and velocity profile in the entrance surface of pump laser are obtained, and the characteristics of SBS induced stress is presented. Calculation shows that the SBS induced surface displacement and velocity can reach the magnitude of 0.1nm and 10m/s respectively when pump intensity is 2.0×1015W/m2, and the corresponding stress exceeds 10MPa.The calculation results by new type equations agree well with those by traditional methods．