Influence of temperature on upconversion multicolor luminescence in Ho^3+/Yb^3+/Tm^3+-doped LiNbO_3 single crystal

The temperature dependence of upconversion luminescence in Ho3+/Yb3+/Tm3+ tri-doped LiNbO3 single crystal was studied at different temperatures from 289 to 773 K under 980 nm excitation. The tri-doped LiNbO3 single crystal offers temperature-dependent color tuning properties, and the white-light emission can be obtained by simply tuning the temperature. In addition, the competition between nonradiative transition and thermal population plays an important role in the upconversion process with temperature increase. This research has implications in the extension of research for optical temperature sensors and multicolor variable temperature display materials.