Spectral characteristics of periodic tunnelling of chirped soliton in nonautonomous system with external potentials

ABSTRACT

We present an exact chirped soliton solution for a nonautonomous system with external potentials and periodic nonlinear barriers/wells (NBs/NWs). Based on the soliton solution, we disclose the interesting spectral features of the chirped solitons through periodic NBs and NWs. In addition to the spectrum being broadened through NBs and being compressed through NWs, we find that distinct spectral characteristics of the chirped soliton appear at the centre, leading and trailing edges of NBs and NWs, which are related to the chirp of the solitons, the period of NBs/NWs and external potentials. When the period of NBs/NWs decreases and the soliton chirp increases, the spectrum appears additional broadening near the leading and trailing edges of both NBs and NWs, but the spectral widths at the centre of both NBs and NWs remain unchanged. Moreover, the linear potential affects the trajectory and the frequency shift of the chirped soliton.

KEYWORDS:

• Periodic tunnelling
• chirped soliton
• nonautonomous NLS equation
• external potentials

Additional information

Funding

This work was supported by the National Natural Science Foundation of China (NSFC) [grant number 61775126], [grant number 61771295]; Natural Science Foundation of Shanxi Province [grant number 201601D011038]; and Shanxi ‘1331 Project’ Key Subjects Construction [1331KSC].