Manufacture and up-conversion luminescence of Er/Yb co-doped silica glass microstructure optical fiber based on the laser sintering technique

Abstract

In this study, the laser sintering technique combined with the stack-capillary-draw method was used to manufacture Er3+/Yb3+ co-doped silica glass microstructure optical fiber for up-conversion (UC) luminescence for the first time. The obtained fiber, whose structure can be maintained well, shows no obvious element diffusion during the fiber-drawing process. The core glass is amorphous without any crystallization, and Er and Yb elements are uniformly distributed throughout the fiber core. Intense upconverted green and red emissions corresponding to (2H11/2, 4S3/2) → 4I15/2 and 4F9/2 → 4I15/2 transitions, respectively, together with an emission corresponding to 2H11/2 → 4I13/2 transition were observed upon the excitation of a 976-nm laser. The intensity of green and red UC luminescence shows a linear dependence on the excitation power which demonstrates that a two-photon absorption process is responsible for the UC process. The results demonstrated the laser sintering technique provides an alternative method to manufacture Er3+/Yb3+ co-doped fiber, which would promote the development of UC luminescent materials.