Temperature Sensing with Up-Converting Submicron-Sized LiNbO₃:Er³⁺/Yb³⁺Particles

Abstract

We present the temperature dependence of the green up-converted luminescence in submicron-sized LiNbO3:Er3+/Yb3+ particles in the range between 12 and 180 °C. It is shown that LiNbO3:Er3+/Yb3+ exhibits a very high sensitivity (S = 0.007/°C at physiological temperature and a maximum value of S = 0.014/°C at 350 °C) that surpasses those previously found for other materials based on Er3+/Yb3+ luminescence, indicating that LiNbO3:Er3+/Yb3+ is a suitable probe for optical temperature sensing through the fluorescence intensity ratio technique. This high sensitivity can be explained using the intrinsic spectroscopic parameters of Er3+ ions in this host.