RESUMO
Sigma and pi polarized absorption spectra of Tm:YVO4 crystal have been measured at room temperature. Considering the difference of the sigma and pi polarized absorption spectra and the changing of the refractive index with different wavelengths, we calculate the intensity parameters of Tm3+ in crystal YVO4 which are omega 2 = 1.9416 x 10(-20) (cm2), omega 4 = 0.1568 x 10(-20) (cm2), omega 6 = 0.3963 x 10(-20) (cm2) by Judd-Ofelt theory. The spectra characteristic parameters, such as radiative transition rates, luminescence branching ratio, total radiative lifetime and integral cross-section are also calculated. The results show that the spontaneous rate of the transition 1D2-->3F4 is much higher than that of the transition 1D2 to other levels.