Experimental generation and control of Raman solitons via Pearcey–Gaussian pulses

Abstract

Soliton self-frequency shift (SSFS) in nonlinear optical fibers is a powerful mechanism for broadband and tunable wavelength conversion. Nevertheless, achieving flexible and efficient control over the resulting Raman solitons remains challenging. Here, we numerically and experimentally demonstrate controlled frequency tuning of Raman solitons using Pearcey–Gaussian (PG) pulses in optical fibers. By tailoring the temporal asymmetry profile and spectral phase modulation of the PG pulse, the driven SSFS provides flexible control of Raman soliton dynamics. We show that a secondary Raman soliton can be efficiently excited not only by a tail-trailing PG pulse, but also by an initially tail-leading PG pulse with an appropriate quadratic spectral chirp. Moreover, introducing this chirp yields a larger and more tunable frequency shift than in the unchirped case, providing precise control over the spectral positions of multiple Raman solitons. Compared with asymmetric Airy-pulse excitation, the PG-based approach offers distinct advantages in both multiple Raman soliton generation and frequency tuning performance. Our results establish PG pulses as a powerful tool for engineering SSFS-driven frequency conversion and are expected to inspire new strategies for soliton control using other classes of structured optical pulses.