Tunable multimode-interference bandpass fiber filter.
We report on a wavelength-tunable filter based on multimode interference (MMI) effects. A typical MMI filter consists of a multimode fiber (MMF) spliced between two single-mode fibers (SMF). The peak wavelength response of the filter exhibits a linear dependence when the length of the MMF is modified. Therefore a capillary tube filled with refractive-index-matching liquid is used to effectively increase the length of the MMF, and thus wavelength tuning is achieved. Using this filter a ring-based tunable erbium-doped fiber laser is demonstrated with a tunability of 30 nm, covering the full C-band.
Antonio-Lopez
J E
JE
Photonics and Optical Physics Laboratory, Optics Department, Instituto Nacional de Astrofísica,Optica y Electrónica, Tonantzintla, Puebla 72000, Mexico.
Castillo-Guzman
A
A
May-Arrioja
D A
DA
Selvas-Aguilar
R
R
Likamwa
P
P