High-pressure optical studies of Y2O3:Eu3+nanoparticles

The fluorescence spectra of Y2O3:Eu3+ nanoparticles have been measured under the pressure of up to 78kbar at room temperature. In this pressure range, a red-shift of 0.02(1)nm/kbar-1 is noticed for the 0-2 line (5D07F2 transition). This shift is explained by the change of negative charge of the surrounding ligands. Compatibility between measured and calculated values for the 0-2 line position was obtained. The luminescence decay curves of the 5D07F2 transition were studied up to 78kbar and were found to behave exponentially for all pressures studied. The fluorescence lifetime for the 0-2 line (5D07F2 transition) slowly decreased with pressure. The pressure effect on for the 0-2 line (5D07F2 transition) was explained by a model which considers the pressure effect on the line position, inter-ionic distance, ion volume and polarizability, molecular volume and polarizability, molecular refractive index and the refractive index medium nmed of the surrounding hydrostatic medium. The fluorescence lifetime calculated by the present model is in close correspondence with the experimental values.