Pressure-and temperature-dependent luminescence from Tm^(3+) ions doped in GdYTaO_(4)

Luminescent properties of Tm^(3+)-doped GdYTaO_(4) are studied for exploring their potential applications in temperature and pressure sensing.Two main emission peaks from ^(3)H_(4)→^(3)H_(6) transition of Tm^(3+)are investigated.Intensity ratio between the two peaks evolves exponentially with temperature and has a highest sensitivity of 0.014 K^(−1) at 32 K.The energy difference between the two peaks increases linearly with pressure increasing at a rate of 0.38 meV/GPa.Intensity ratio between the two peaks and their emission lifetimes are also analyzed for discussing the pressure-induced variation of the sample structure.Moreover,Raman spectra recorded under high pressures indicate an isostructural phase transition of GdYTaO_(4) occurring at 4.46 GPa.