Tunable narrow linewidth Tm3+-doped silica fiber laser with an intracavity taper

Using an intracavity long fiber taper, the 793 nm diode laser (LD) clad-pumped tunable narrow linewidth Tm3+-doped silica fiber laser was realized. The intracavity long taper was fabricated directly on the Tm3+-doped fiber by heating and stretching method, and located several centimeters from the output fiber end. The fiber laser cavity was combined by the fiber end Fresnel reflection and a dichroic. The fiber laser had a maximal output power of 5.86 W at 1927.2 nm, with a narrow linewidth of 148 pm. By stretching or bending the taper, the output laser center wavelength could be tuned from 1910.6 nm to 1958.1 nm with a variable spectrum width ranging from 92 – 148 pm