MULTIPLE-HUMPED BRIGHT SOLITARY WAVES IN 2ND-ORDER NONLINEAR MEDIA

The propagation of multiple-humped bright solitary waves in a diffract ive medium with second-order nonlinearity is studied. It is shown that the multiple-humped bright solitary waves occur only for negative pha se mismatches in a small interval of nonlinear wave numbers shifts and above a certain threshold energy flow. Numerical experiments reveal t hat the multiple-humped stationary solitary waves are unstable on prop agation. The evolution of multiple-humped solitary waves shows that th e instability leads to one of the following three scenarios of the sol itary wave dynamics: (1) the spreading of the solitary wave, (2) the f ormation of a single-humped solitary wave from a multiple-humped solit ary wave in a fusion-like process, and (3) the decay of the multiple-h umped solitary waves into several fragments consisting of single-humpe d solitary waves. (C) 1996 Society of Photo-Optical Instrumentation En gineers.