Refractive index profile of fused-tapered fiber couplers

Multimode interference tapered fiber refractive index sensors.

Real-time monitoring of the fabrication process of tapering down a multimode-interference-based fiber structure is presented. The device is composed of a pure silica multimode fiber (MMF) with an initial 125 μm diameter spliced between two single-mode fibers. The process allows a thin MMF with adjustable parameters to obtain a high signal transmittance, arising from constructive interference am...

Nondestructive measurement of refractive index profile for holey fiber preforms.

A non-destructive technique is presented to determine the refractive index profile of holey fiber preforms. The holes are filled with index matching oil and the holey preform deflection data is measured. An improved optical path-length formula and back projection method is used to reconstruct the two-dimensional filled holey fiber preform refractive index distribution.

Optical fiber refractive index profile synthesis from near field

Abstract – A new and accurate refractive index profile synthesis method for optical waveguides is demonstrated using the transmitted near electric field data. This method is based on an inverse transmission line technique. From Maxwell’s equations, we derive a transmission line equivalent circuit for the refractive index profile of a cylindrical dielectric waveguide. We demonstrate how to use t...

Fused Fiber Couplers: Basic Theory and Automated Fabrication

Soliton controlling, switching, and splitting in nonlinear fused-fiber couplers

We propose an exactly solvable model of soliton-based pulse control that describes the physically important situation when the soliton period is much longer than the length of the coupling region in a nonlinear fiber coupler. This case can occur, e.g., in fused-fiber couplers. We demonstrate that the problem of soliton interaction and switching in such a coupler can be reduced to a linear relat...