A study on ratiometric thermometry based on upconversion emissions of erbium ions in gadolinium gallium garnet single-crystal

We have studied ratiometric thermometry based on six fluorescence intensity ratios (FIR) involving two component peaks of 530 nm emission band and three component peaks of 550 nm emission band of erbium-doped gadolinium gallium garnet single-crystal. All the six EIR schemes display higher, slightly different relative sensitivities and thermal resolutions. The temperature is overall and reliably determined by the six EIR schemes. In addition, the crystal shows strong green upconversion emissions and thermally stable spectral structure, it is thus a promising material for the ratiometric thermometry. The multiple ratiometric thermometry based on the material has highly efficient performance, and is thus promising for reliable temperature detection in electromagnetically and/or thermally harsh environments and some industrial processes.386