Growth and red-orange emission of Sm~(3+) doped SrAl_(12)O_(19) single crystals

摘要

Sm:SrAl12O19 (Sm:SRA) single crystals with dopant concentration of 1 and 8 at.% have been successfully grown by the Czochralski method. Polarized absorption spectra, emission spectra, as well as the lifetime measurements were performed. The absorption cross-section was calculated to be 1.97 x 10(-20) cm(2) at 404 nm for sigma polarization and 1.13 x 10(-20) cm(-2) at 405 nm for pi polarization, respectively. The highest emission cross-section at 593 nm was calculated to be 0.58 x 10(-21) cm(2) for sigma polarization and 0.45 x 10(-21) cm(2) for pi polarization, with full width at half maximum (FWHM) of 7.73 nm and 7.42 nm, respectively. Judd-Ofelt (JO) intensity parameters (Omega(2), Omega(4) and Omega(6)) and radiative properties for the important luminescent level of Sm3+ ions were derived by using the polarized absorption spectra of 8 at.% Sm:SrAl12O19. The fluorescence lifetime of 1 at.% and 8 at.% Sm:SrAl12O19 crystals were calculated to be 2.83 ms and 2.11 ms, respectively. The results indicate that the Sm:SRA crystal would be potential laser material for red-orange oscillation pumped by commercially 405 nm laser diode.