Design of elliptical few-mode fibers for mode-coupling-free parametric amplification

摘要

In a few-mode optical parametric amplifier, which is based on intramode four-wave mixing, mode coupling between degenerate modes causes gain reduction, and the signal gain varies depending on its mode pattern. Hence, it is highly desirable to eliminate degenerate mode coupling in a few-mode parametric amplifier. We propose an elliptical-core dispersion-shifted few-mode fiber to suppress the mode coupling between degenerate modes. Simulation results show the fiber can be used for a four-mode parametric amplifier with over 30 nm gain bandwidth across the C-band in a 300-m-long fiber. (C) 2018 Optical Society of America