The Japan Society of Applied Physics

2023 International Conference on Solid State Devices and Materials

2023 International Conference on Solid State Devices and Materials

2023年9月5日 〜 2023年10月31日
Nagoya Congress Center

14:15 〜 14:30

[H-1-02] Optical Detection of Trace Amounts of Er Ions in Silicon-based Rare Earth Oxide Thin Film Waveguides

○Shoichiro Yasui1,2, Tomohiro Inaba1, Kenichi Hitachi1, Atsushi Ishizawa3, Reina Kaji2, Takehiko Tawara4, Satoru Adachi2, Xuejun Xu1, Haruki Sanada1 (1. NTT Basic Res. Lab., NTT Corp. (Japan), 2. Graduate School of Eng., Hokkaido Univ. (Japan), 3. College of Indus. Tech., Nihon Univ. (Japan), 4. College of Eng., Nihon Univ. (Japan))

https://doi.org/10.7567/SSDM.2023.H-1-02

We detected the photoluminescence (PL) from trace amounts of erbium (Er) ions in non-doped Gd2O3 thin films by using a waveguide structure. The Stark level structure was identified by photoluminescence excitation (PLE) spectroscopy, and the optical relaxation lifetime was evaluated by time-resolved photoluminescence (TR-PL) measurements. The PLE spectra show that the energy transfer between Er ions is significantly suppressed compared to the highly Er-doped Gd2O3 thin film. The obtained optical relaxation lifetime is reduced by an order of magnitude compared to that in the Er:Gd2O3 thin film possibly due to the Purcell effect in the highly confined waveguide structure. These results reveal the optical properties of Er3+ ions in the Gd2O3 thin films with ultra-low doping concentration and pave the way towards the optical addressing of single Er3+ ions in the films.