Optical and electron paramagnetic resonance studies of Fe impurities in yttrium aluminum garnet crystals.
Optical and electron paramagnetic resonance studies of Fe impurities in yttrium aluminum garnet crystals.
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DOI：
10.1103/physrevb.38.8555
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发表时间：
1988-11
期刊：
影响因子：
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通讯作者：
C. Y. Chen;G. J. Pogatshnik;Y. Chen;M. Kokta
中科院分区：
文献类型：
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作者：
C. Y. Chen;G. J. Pogatshnik;Y. Chen;M. Kokta
采用光吸收和电子顺磁共振（EPR）技术研究了钇铝石榴石（YAG）晶体中的铁杂质。含Fe/sup 3+/的YAG晶体由于其低对称性而呈现出许多EPR谱线。Fe/sup 3+/离子在八面体和四面体位置被鉴定。EPR和光吸收测量的相关研究表明，在255 nm处的吸收带是一个复合的电荷转移带，它是由两个对称位置上的取代态Fe/sup 3+/的贡献组成的。进行了高达1700 K的氧化和还原实验。前者使Fe/sup 3+/浓度增加，后者使Fe/sup 2+/浓度降低，Fe/sup 3+/转化为Fe/sup 3+/的热活化能为3.0 ± 0.3eV。
Optical-absorption and electron paramagnetic resonance (EPR) techniques were used to study iron impurities in yttrium aluminum garnet (YAG) crystals. Due to its low symmetry, YAG containing Fe/sup 3+/ exhibited many EPR lines. Fe/sup 3+/ ions in octahedral and tetrahedral sites were identified. A correlation study involving both EPR and optical-absorption measurements indicated that the absorption band at 255 nm, which had been previously attributed to an Fe/sup 3+/ charge-transfer band, was a composite charge-transfer band made up of contributions from substitutional Fe/sup 3+/ at both symmetry sites. Oxidation and reduction experiments up to 1700 K were performed. The former increased the Fe/sup 3+/ concentration, and the latter diminished it. Conversion of Fe/sup 2+/ to Fe/sup 3+/ was governed by a thermal activation energy of 3.0 +- 0.3 eV.