Bright Green Emission in Ho⁺³-Yb⁺³ Co-Doped Bi_1/2Na_1/2TiO₃ Ferroelectric Ceramics and the Optical Thermometry Behavior

Abstract

Ho⁺³-Yb⁺³ co-doped bismuth titanate ferroelectric ceramics were prepared by the solid-state reaction method. A bright green emission is observed at room temperature, which ascribed to ⁵F₄+⁵S₂ →⁵I₈ transition. The dependence of the emission intensity on the pumping power indicated that the up-conversion emission in the ceramics was a two-photon process. Additionally, an optical temperature sensor based on the blue emission from the ⁵F_2,3/³K₈ and ⁵F₁/⁵G₆ states of Ho³⁺ ions has been developed. In the temperature range of 273–573 K, the maximum sensitivity of about 0.0009 K⁻¹is obtained. Our study suggests that Ho³⁺ and Yb³⁺ co-doped Bi_1/2Na_1/2TiO₃ (NBT) ceramics can be applied to the fabrication of new photoluminescence ferroelectric ceramics devices and of the optical temperature sensors.

Keywords:

• Up-conversion
• blue emissions
• fluorescence intensity ratio
• temperature sensor

Funding

This work was supported by the Natural Science Foundation of China (Nos. 51072136, 50932007).