Optimization of soliton amplitude in dispersion-decreasing nonlinear optical fibers

The compression of a cw into a periodic train of noninteracting solitons by a dispersion-decreasing fiber is investigated with a variational method. T o model the evolution from the cw to the soliton train, an elliptic-functio n-based expression is used as the trial function in the averaged Lagrangian . Both a continuous dispersion variation and a step dispersion variation in the fiber are considered. By use of an optimization method based on the ap proximate variational equations, the optimal dispersion profile required fo r achieving maximum pulse compression in a fixed length of fiber is determi ned. The solutions of the approximate equations are compared with full nume rical solutions of the governing nonlinear Schrodinger equation, and good a greement is found. (C) 1999 Optical Society of America [S0740-3224(99)01103 -0]. OCIS codes: 190.4370, 190.4360, 190.5530, 060.6370, 060.5530.