Analysis About Low Differential Mode Delay Based on Wavelength Dependence of Effective Refractive Index in Few Mode Fibers Around 1550nm

Abstract

An approximate condition for obtaining low differential mode delay (DMD) over the wavelength range in the few mode fiber (FMF) is proposed and verified numerically based on the wavelength dependence of effective refractive index ${\left(n_{eff}\right)}$. Using this technique, optimization about a published 4-LP-mode FMF for lower DMD is displayed. The final ${\max}\vert \text{DMD}\vert$ and the DMD value at 1550nm can decrease 40.35% and 24.92%, respectively. The presented method based on the wavelength dependence of ${n_{eff}}$ can show one potential way to directly evaluated the DMD values in the FMF.