Cr3+掺杂的Ca3Al2Ge3O12石榴石的光谱性质

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。

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

The spectral properties of Cr³⁺ doped calcium aluminium germanate garnet (Ca₃Al₂Ge₃O₁₂) have been investigated. Dependence of the zero-phonon-line positions from Cr³⁺in the inequivalent crystallographic sites has been studied as a function of concentration and temperature. The crystal field intensity parameters Dq and Racah parameters were deviated by analyzing the absorption and emission spectra. The fine structure of Cr³⁺in Ca₃Al₂Ge₃O₁₂ at low temperature has been assigned as a vibronic progression in two kinds of phonon with energies ω₁(A)=165～170cm^-1, ω₂(A)=200cm^-1 and ω₁(B)=130～135cm^-1, ω₂(B)=185～190cm^-1. The luminescence decay behavior of Cr³⁺different transitions has been investigated upon red laser excitation and showing single exponential decay curves.