Eu3+-based dual-excitation single-emission luminescent ratiometric thermometry

Recently, single-band ratiometric (SBR) thermometry becomes a hot-spot in the research field of optical thermometry. Here we propose a new SBR thermometry by combining the temperature-induced red shift of charge transfer state (CTS) of W-O and Eu-O with the ground state absorption (GSA) and excited state absorption (ESA) of Eu3+. The emitting intensity of the D-5(0)-F-7(2) transition of Eu3+ is monitored under CTS, GSA and ESA excitations at different temperatures. It is found that the SBR thermometry, depending on the combination of [GSA+ CTS] of Eu3+ doped calcium tungstate, has the highest relative sensitivity of 1.25% K-1 at 573 K, higher than conventional luminescent ratiometric thermometry such as the 2H(11/2) and S-4(3/2) thermally coupled states of Er3+. (c) 2021 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement

Automated summary

A new single-band ratiometric (SBR) thermometry is proposed by combining the temperature-induced red shift of charge transfer state (CTS) of W-O and Eu-O with the ground state absorption (GSA) and excited state absorption (ESA) of Eu3+. The SBR thermometry of Eu3+ doped calcium tungstate shows the highest relative sensitivity of 1.25% K-1 at 573K, surpassing conventional luminescent ratiometric thermometry methods.