Probing the dispersive properties of optical fibers with an array of femtosecond-written fiber Bragg gratings

TL;DR

This paper introduces a novel, efficient method using femtosecond-written fiber Bragg gratings to accurately measure the dispersive properties and effective refractive index of various optical fibers across a broad spectral range from visible to mid-infrared.

Contribution

The paper presents a new technique employing an array of fiber Bragg gratings written with femtosecond laser technology to determine fiber dispersion over a wide spectrum.

Findings

Validated method on standard silica fiber

Applied technique to fluoride glass fibers

Measured dispersion from 550 to 4800 nm

Abstract

We propose an efficient method to determine the effective refractive index of step-index optical fibers from the visible to the mid-IR and thus allowing to infer their dispersive properties over a broad spectral range. The validity of the method, based on the writing of an array of fiber Bragg gratings (FBGs) with known periods using the fs scanning phase mask technique, is first confirmed with a standard silica fiber, then applied to various fluoride glass fibers to determine their effective refractive index and dispersion over more than three octaves, i.e. from 550 to 4800 nm.