Luminescent properties of Er3+/Yb3+ co-doped oxyfluoride glass ceramic microsphere with the tapered fiber-microsphere coupling system

Abstract

We prepare Er3+/Yb3+ co-doped oxyfluoride glass ceramic samples by high temperature calcination method (41.2SiO2-29.4Al2O3-17.6Na2CO3-11.8LaF3-0.5ErF3-2.5 YbF3), and also fabricate transparent microspheres each with a handle. We propose a new method of studying the luminescent properties of Er3+/Yb3+ co-doped oxyfluoride glass ceramic with the tapered fiber-microsphere coupling system. The method has characteristics such as low excitation optical power, easy preparation and testing. We couple the 976 nm laser into the microspheres with the coupler of optical tapered fiber, then the fluorescence and laser are connected to spectrum analyzer with the optical tapered fiber. The strong up-conversion fluorescences at 522, 545 and 657 nm are obtained, and the laser oscillation spectra generated by Er3+ ions at 1562 nm are also measured. The up-conversion luminescence mechanism of Er3+, the mechanism of high luminescence efficiency in Er3+/Yb3+ co-doped oxyfluoride glass ceramic microsphere, and the mechanism of higher laser oscillation threshold in the oxyfluoride glass ceramic microsphere than in the SiO2 matrix microsphere are all analyzed.