强烈涌现的八面体修饰与Al兴奋剂及其对NdNiO3薄膜电子传输的影响
Ketan S Navale1, Diptanshu Basak1, Ekta Yadav1
1Department of Physics, Indian Institute of Technology (IIT) Indore, Simrol, Khandwa Road, Indore 453352, India.
概括
在基酸 (NdNiO3) 薄膜中的兴奋剂诱导BO6八面体中的抗拉伸模式,与增强的金属绝缘体过渡温度 (TMI) 相对应. 这项研究探讨了兴奋剂和厚度对电子传输特性的影响.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 固态化学 固态化学
背景情况:
- 新尼基酸盐 (NdNiO3) 呈现温度依赖的电子传输和金属绝缘体过渡 (TMI).
- 在NdNiO3薄膜中的TMI对化学替代和应变敏感.
- 了解这些灵敏度对于调整材料特性至关重要.
研究的目的:
- 研究 (Al) 兴奋剂对 NdNiO3 薄膜中的电子传输和金属绝缘体过渡的影响.
- 探索结构修改 (八面体抗拉伸) 和电气性能之间的关系.
- 为了检查薄膜厚度对这些特性的影响.
主要方法:
- 脉冲激光沉积 (PLD) 技术在LAO (001) 基板上合成NdNi(1-x) AlxO3薄膜,具有不同的Al兴奋剂 (x=0-0.50) 和厚度 (10-200 nm).
- 射线光电子光谱 (XPS) 用于分析Ni的氧化状态.
- 拉曼光谱 (温度依赖) 和使用巴尔干斯基和格鲁尼森模型进行分析,以研究结构振动和不和性.
主要成果:
- 在Ni位点的Al兴奋剂改变了Ni的氧化状态,并在693厘米-1处引入了Raman模式,与BO6八面体抗拉伸相关.
- 抗拉伸模式的强度随着Al兴奋剂的增加而增加,与增强的TMI相关.
- 增加Al兴奋剂 (x >= 0.20) 会导致室温以下的绝缘行为;薄膜厚度会影响电阻力和抗拉伸模式.
结论:
- 在Al-doped NdNiO3薄膜中观察到的抗拉伸模式与Al替代直接相关.
- 这种结构修改是驱动绝缘行为和增加TMI的关键因素.
- 控制Al兴奋剂和薄膜厚度提供了一条调整NdNiO3基材料电子性质的途径.
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