Upconversion luminescence and effect of pump power on optical thermometry of Yb3+/Er3+ co-doped YOF self-crystallization glass ceramics

The optical thermometry based on the fluorescence intensity ratio (FIR) method overcomes many disadvantages of traditional contact temperature measurement, and appropriate host materials can improve the temperature sensing sensitivity. Herein, Yb3+/Er3+ co-doped YOF glass ceramics (GC) were prepared, and the luminescence and temperature sensing properties were researched under 980 nm excitation with different pump power. The FIR of thermal couple energy level (TCEL) and non-thermal couple energy level (NTCEL) was used to evaluate the temperature sensing sensitivity. The higher pump power results in a decrease in relative sensitivity (SR) due to the thermal effect and increased rate of energy transfer and non-radiative relaxation process between dopants and host. The maximum relative sensitivity of this sample reaches 1.59 × 10−2 K−1 at 310 K with a pump power of 0.2 W, which shows that this GC is a prospective application in optical thermometry.