Cr4+-doped Li2MgSiO4: a new potential tunable laser material with room temperature fluorescence lifetime greater than 100 um

摘要

This paper deals with the synthesis and optical properties of a new compound Cr$+4$PLU$/:Li$-2$/MgSiO$-4$/ which looks promising for tunable lasers applications. The emission is intensive and centered around 1190 nm, covering the range 1100 to 1400 nm. At low temperature, the fluorescence spectrum represents two zero phonon lines at 1109 nm and 1205 nm, attributed to the $+3$/T$-2$/ and $+1$/E levels, $+1$/E lies 712 cm$+$MIN@1$/ below $+3$/T$-2$/. The fluorescence lifetime exceed 100 s at room temperature and 400 $mu@s at 50 K. This is roughly one order of magnitude higher than the values obtained for all the others Cr$+4$PLU$/ activated materials. A thermalization between the $+3$/T$-2$/ and $+1$/E levels can explain these outstanding properties.