Optical properties of Er3+ heavily doped silica glass fabricated by zeolite method

We successfully fabricated heavily Er3+-doped silica glasses (ErZSG) by a zeolite method and measured their optical properties such as absorption, fluorescence and excitation spectra, and lifetime. The samples' lifetime was measured as 4.26 +/- 0.02 msec at 9,600 wtppm. In order to reveal the quantum efficiency eta, we also examined the radiative lifetimes of the ErZSGs by Judd-Ofelt analysis, and then the quantum efficiency was evaluated to be 45.1 +/- 3.3% at 9,600 wtppm, which is a high enough value for constructing a short-length laser oscillator. The ErZSG-based short-length laser oscillator is an attractive light source for such applications as medicine, biology, and metrology, and it is especially promising as a light source of LiDAR.