Ultrathin transition-metal oxide films: Thickness dependence of the electronic structure and local geometry in MnO
Ultrathin transition-metal oxide films: Thickness dependence of the electronic structure and local geometry in MnO
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超薄过渡金属氧化物薄膜：MnO 中电子结构和局部几何形状的厚度依赖性
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发表时间：
2007
期刊：
影响因子：
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通讯作者：
T. Chassé
中科院分区：
文献类型：
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作者：
M. Nagel;I. Biswas;P. Nagel;E. Pellegrin;S. Schuppler;H. Peisert;T. Chassé
利用x射线吸收光谱和x射线光发射光谱研究了银衬底上超薄氧化锰薄膜厚度的函数关系。通过结合这些技术，可以更好地理解局部几何形状和电子结构。研究发现，超薄膜的电子和几何性质与体材有显著的不同。通过偏振相关的x射线吸收测量揭示了氧化膜的四方畸变；随着膜厚的增加，这种程度逐渐减小。加热引起的外延氧化层的松弛也导致了四方界面应变的减小。超薄氧化锰薄膜的电子结构在价带区随厚度的变化而变化。
Ultrathin manganese monoxide films on silver substrates are studied as a function of the thickness using x-ray absorption spectroscopy and x-ray photoemission spectroscopy. By combining these techniques, an improved understanding of both the local geometry and the electronic structure is achieved. It was found that both electronic and geometric properties in ultrathin films differ significantly from the bulk. A tetragonal distortion of the oxide films is revealed by polarization-dependent x-ray absorption measurements; the extent is decreasing gradually with increasing film thickness. A relaxation of an epitaxial oxide layer induced by heating also leads to a decrease of the tetragonal interface strain. The electronic structure of ultrathin manganese oxide films changes in the valence-band region with dependence on thickness.