An adaptive algorithm for strongly chirped pulses propagating in optical fibers

Chirp, especially strong chirp, can be used to control the pulses in optical fibers, but it makes numerical simulation difficult by using the time-domain beam propagation method (TD-BPM) because of more sampling data requirements. In this paper, we present a modified beam propagation method (M-BPM) to efficiently simulate the propagation of strongly chirped pulses along an optical fiber. The validity of the M-BPM is demonstrated both theoretically and numerically. Numerical simulations show that the number of samples in time necessary to simulate the chirped pulse propagation by the TD-BPM varies linearly with the initial chirp parameter, but that of the M-BPM is the same one would need to simulate the propagation of the envelope without the initial chirp. In addition, the closer the propagation distance is to the temporal focal length, the more efficient the M-BPM comparing with the TD-BPM is.

► We present a modified beam propagation method (M-BPM) for nonlinear propagation of chirped pulses.
► The validity of M-BPM is confirmed by analytic analysis and numerical simulations.
► The required sampling number of M-BPM is the same as the chirp-free pulse.
► The computational efficiency of M-BPM is improved with the chirp parameter.