Improved Intrapulse Raman Scattering Control via Asymmetric Airy Pulses

We study the soliton self-frequency shift (SSFS) initiated by Airy pulses in a fiber, and demonstrate the versatility of these asymmetric pulses in controlling the frequency tuning of laser light. The time asymmetric features of input Airy pulses, with either leading or trailing oscillatory tails (relative to the main lobe), are revealed in the output primary and secondary Raman SSFS as a result of different soliton fission processes. Control of the Raman frequency shifts can be achieved by input pulse time reversal, or more simply offsetting the spectral phase (equivalently introducing linear chirps) of both tail-leading and –trailing Airy pulses. Such a flexible method has key feasibility and smoothness advantages for frequency tuning in contrast with using a pre-chirped Gaussian-like pulse. Furthermore, we demonstrate that linear chirping the input Airy pulses can be employed to control multi-color Raman solitons, with enhanced tunability for the tail-leading case. Our theoretical studies are well confirmed by experimental observations.