在高氧化物中定位振动模式.
C M Wilson1, R Ganesh1, D A Crandles1
1Department of Physics, Brock University, St. Catharines, Ontario L2S 3A1, Canada.
概括
高氧化物 (HEO) 呈现出独特的混乱和局部的振动刺激. 这项研究探讨了原型HEO中的音声本地化,揭示了波形和本地化模式,并建议HEO作为安德森本地化研究的平台.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
背景情况:
- 高氧化物 (HEO) 是一种具有结晶秩序和显著原子混乱的新型材料.
- 众所周知,像玻璃和合金这样的无序固体会表现出局部的振动激发.
- 了解HEO中的语音行为对于它们的技术应用至关重要.
研究的目的:
- 为了研究在原型岩盐结构的HEO,Mg_{0.2}$Co$_{0.2}$Ni$_{0.2}$Cu$_{0.2}$Zn$_{0.2}$O.O中引起的语音局部化的现象.
- 为了建模和分析这个HEO的音声激发光谱.
- 探索在高等教育机构中增强音声本地化策略.
主要方法:
- 通过适应母二元氧化物属性,开发了一种氧原子间潜力的模型.
- 与实验晶体结构和光导率数据对模型进行了验证.
- 分析了语音频谱,包括参与率和相关振幅,以确定局部模式.
主要成果:
- HEO的语音频谱在低能量的情况下呈现波形传播模式,在高能量的情况下呈现局部模式.
- 确定了局部化的特征,例如参与率和相关幅度.
- 一种假设的高氧化氧化物证明了增强的局部化,在中频谱中增加了额外的模式.
结论:
- 高密度物质中的障碍可以诱导局部的振动激发,与传统的无序材料不同.
- 增加质量障碍提供了一条途径,以增强HEO中的声子局部化.
- HEO 作为一个有前途的实验平台,用于研究音声的安德森本地化.
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