Crystal growth and temperature dependence of luminescence characteristics of Pr3+ and Tb3+ doped solid-solution sesquioxide single crystals

Abstract

In recent decades, optical thermometry has gained significant attention due to its promising properties, such as non-contact measurement, temperature mapping and immunity to electromagnetic interference. It overcomes the limitations of conventional temperature measurement methods and offers additional benefits. However, the widespread adoption of optical thermometry requires an expanded operating temperature range and improved sensitivity. Therefore, in this study, we focused on solid-solution sesquioxides, which are expected not only to enable the growth of single crystals with a cubic structure but also to allow for a wider selection of luminescence centers. We evaluated the applicability of (Lu, Y, Sc)₂O₃ single crystals doped with Pr³⁺ and Tb³⁺, which exhibit different temperature dependent behaviors, for optical thermometry. The optical temperature sensing properties evaluated using the fluorescence lifetime method revealed a maximal relative sensitivity of 1.53% K⁻¹ in the temperature range of 78–790 K for Pr³⁺, Tb³⁺:(Lu, Y, Sc)₂O₃. These results suggest that (Lu, Y, Sc)₂O₃ co-doped with Pr³⁺ and Tb³⁺ is a promising candidate for optical thermometry.