Multi-wavelength switching of an erbium-doped fiber ring laser based on the cross-sensitivities’ features of tapered fiber filters

In this work, multi-wavelength switching of laser emission of an erbium-doped fiber ring laser (EDFRL) is reported, by exploiting the cross-sensitivities’ features (curvature and surrounding RI) of concatenated tapered fibers that form an interferometer. The curvature applied in the fiber interferometer switches the multi-wavelength laser emission in the range ~1544.66–1565.72 nm. The combination of curvature and substances with different refractive index (RI) allows switching the multi-wavelength emission to shorter wavelengths, in the range ~1530.62–1565 nm. In this proposal, the use of the cross-sensitivities’ features extends the multi-wavelength emission in the operating C-band.