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… (More)
A widely tunable erbium-doped all-fiber laser has been demonstrated. The tunable mechanism is based on a novel tunable filter using multimode interference effects (MMI). The tunable MMI filter was applied to fabricate a tunable erbium-doped fiber laser via a standard ring cavity. A tuning range of 60 nm was obtained, ranging from 1549 nm to 1609 nm, with a… (More)
A tunable dual-wavelength ytterbium doped photonic crystal fiber laser based on a Mach-Zehnder interferometer is presented. The laser tunes from 1026nm to 1034nm by controlling the birefringence with a linewidth of 0.007nm and a contrast of 40dB.