Organic dye-loaded reduced titanium dioxide as a broadband saturable absorber for ultrafast fiber lasers.

As a rising star among metal oxide nanomaterials, titanium dioxide (TiO) has been widely investigated and employed in optical applications because of its excellent optical properties. In this work, we demonstrate the efficient and broadband nonlinear photonic properties of methylene blue (MB)-loaded reduced TiO (TiO-MB) and explore the performance of a TiO-MB-microfiber photonic device in broadband ultrafast photonics. Within an erbium-doped fiber laser (EDFL) system, utilizing the TiO-MB-microfiber photonic device as a saturable absorber (SA), steady mode-locked pulses together with chaotic pulses were successfully achieved at the wavelength of 1.