Optical properties of nonstoichiometric fluorite crystals doped with Nd3+ and Pr3+ in 1.3-um spectral range

摘要

Abstract: Optical properties with more than 120 multicomponent nonstoichiometric fluoride crystals M$+$PLU@,2$PLU$/F$-m$/-R$+3$PLU$/F$-n$/ with CaF$-2$/ structure doped with Nd$+3$PLU$/ and Pr$+3$PLU$/ were studied especially in 1.3 $mu@m spectral range which is promising for operation in the second telecommunication window. The direct measurements of excited state absorption and single pass gain in 1.3 $mu@m range have been carried out for Na$-0.4$/Y$-0.6$/F$-2.2$/ and Ca$-0.9$/Y$-0.1$/F$-2.1$/ crystals. The effective cross-sections and halfwidth of gain band have been determined ($sigma$-max$/ $EQ 2.2 $POM 0.7 10$+$MIN@21$/ cm$+2$/, $Delta $EQ 40 cm$+$MIN@1$/ and $sigma$-max$/ $EQ 4.5 $POM 0.9 10$+$MIN@21$/ cm$+2$/, $delta $EQ 60 cm$+$MIN@1$/, respectively). The line's strengths in Ba$-1$MIN@x$/Gd$-x$/F$- 2$PLU@x$/:Pr crystals has been found to be raised in nonstoichiometric crystals in comparison with stoichiometric ones due to formation of another type of optical centers. The energy of destruction of these Pr$+3$PLU$/ positions has been determined to be 280 cm$+$MIN@1$/. The mean decay rate of Yb$+3$PLU$/ is found to be proportional to the multiplying of Yb$+3$PLU$/ and Pr$+3$PLU$/ concentrations in Yb$+3$PLU$/ sensibilized BaGdF:Yb,Pr and PbCdF:Yb,Pr crystals. The optimal concentrations of Yb and Pr and single pass gain coefficient have been calculated. !15