Cr^(3+)掺杂的Ca_3Al_2Ge_3O_(12)石榴石的光谱性质

SPECTRAL PROPERTIES OF THE Cr 3+ DOPED Ca 3Al 2Ge 3O 12 GARNETS

在此报告钙铝锗石榴石Ｃａ３Ａｌ２Ｇｅ３Ｏ１２中Ｃｒ３＋离子的光谱特性，依据不同浓度的样品在不同温度下发射光谱的实验结果，分析了不等价Ｃｒ３＋发光中心零声子线Ｒ１，Ｒ２的位置变化情况．通过对Ｃｒ３＋吸收和发射光谱的分析，估算了Ｃｒ３＋所处格位的晶场强度参数Ｄｑ和Ｒａｃａｈ参数，同时，对低温下Ｃｒ３＋Ｒ线边带振动光谱的精细结构的起因进行了分析和指认．在室温和低温下测得Ｃｒ３＋的４Ｔ２→４Ａ２和２Ｅ→４Ａ２能级跃迁的荧光衰减为单指数规律．

The spectral properties of Cr 3+ doped calcium aluminium germanate garnet (Ca 3Al 2Ge 3O 12 ) have been investigated. Dependence of the zero phonon line positions from Cr 3+ in the inequivalent crystallographic sites has been studied as a function of concentration and temperature. The crystal field intensity parameters D q and Racah parameters were deviated by analyzing the absorption and emission spectra. The fine structure of Cr 3+ in Ca 3Al 2Ge 3O 12 at low temperature has been assigned as a vibronic progression in two kinds of phonon with energies ω 1(A)=165～170cm -1 , ω 2(A)=200cm -1 and ω 1(B)=130～135cm -1 , ω 2(B)=185～190cm -1 . The luminescence decay behavior of Cr 3+ different transitions has been investigated upon red laser excitation and showing single exponential decay curves.