Robust operation of a dual-core fiber ring laser

This is the authors' abstract. We don't add key points for this paper.

A passively mode-locked dual-core fiber ring laser, similar to that first proposed by Winful and Walton [ Opt. Lett.17, 1688 ( 1992)], is numerically simulated, incorporating losses and higher-order effects. Ultrashort hyperbolic secantlike pulses with negligible chirp are generated by this laser. The laser operation is robust but not self-starting; lasing action is found even when stimulated Raman scattering and changes in the cavity length are included. The pulse amplitude, phase, and pulse spectrum are discussed.