Evaluation of rare earth doped silica sub-micrometric spheres as optically controlled temperature sensors

We report on the evaluation of rare earth (Er3+, Eu3+, and Tb3+ ions) SiO2 sub-micrometric spheres as potential optically controllable temperature sensors. Details about fabrication, optical manipulation and spectroscopic characterization of the sub-micrometric spheres are presented. The fluorescence properties of the micros-spheres in the biological range (25–60 °C) have been systematically investigated. From this systematic study, the thermal resolution potentially achieved in each case has been determined and compared to previous works