石英中Al3+-空穴取向变化弛豫过程中的红外发散响应

基于α石英的晶体结构，将红外发散响应模型和双势阱模型应用到含Ａｌ杂质的α石英中Ａｌ³⁺－空穴的取向变化弛豫过程，研究其低温介电损耗特性，结果表明Ｔ＜６．５Ｋ时，介电损耗的主要贡献来自于单声子助隧道弛豫过程；Ｔ＞１０Ｋ时，主要贡献来自于热跃迁弛豫过程；而在中间温区，介电损耗是两种过程的迭加，同一弛豫体不同的弛豫过程对应于不同的红外发散响应，还讨论了同一弛豫体引起的超声弛豫损耗。 关键词：

INFRARED DIVERGENCE RESPONSE IN REORIENTATIONAL RELAXATION PROCESS OF Al3+-HOLE IN α QUARTZ

The infrared divergence response theory is applied to reorientational relaxation process of Al³⁺-hole in α-quartz containing Al impurity to study the behaviour of low temperature dielectric relaxation loss properties in this system. Our calculation results showed that the single phononassisted tunneling process makes the main contribution to the dielectric loss for T<6.5 K; while for T>10 K, the thermally activated relaxation process dominates the dielectric loss; as for 6.5 K < T<10 K, the dielectric loss is the superposition of the two relaxation process. It is pointed out that for the same relaxation unit, different relaxation process may have different infrared divergence response. The ultrasonic relaxation loss properties induced by the same relaxation unit is also discussed.