Optical properties of Nd3+ ions doped GdTaO4 for pressure and temperature sensing

Pressure - and temperature-dependent luminescence properties of 3F3/2 → 4I9/2 transition of Nd3+:GdTaO4 were studied for potential applications in optical sensing. Two isolated emission lines correspond to 3F3/2(R2, 1) → 4I9/2(Z5) transitions, locates at 920 and 927 nm under ambient condition, are very sensitive to pressure with coefficients of −15.6 and −14.5 cm−1/GPa determined in a pressure range up to about 9 GPa. The luminescence intensity ratio between the two emission lines exhibits a large dependence with temperature in a range from 80 to 620 K, the corresponding temperature sensitivity at room temperature is similar to that of Nd3+:YAG. These advantages, together with the other observed features of high stable position relationship under pressure and low thermal shifts for the two emission lines indicate that, Nd3+:GdTaO4 is a promising candidate to be used as pressure and temperature sensors in the near-infrared spectral range.