Electronic band structure of Ti2O3 thin films studied by angle-resolved photoemission spectroscopy
Electronic band structure of Ti2O3 thin films studied by angle-resolved photoemission spectroscopy
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角分辨光电子能谱研究 Ti2O3 薄膜的电子能带结构
DOI：
10.1103/physrevb.105.235137
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发表时间：
2022
影响因子：
3.7
通讯作者：
Kumigashira Hiroshi
中科院分区：
文献类型：
--
作者：
Hasegawa Naoto;Yoshimatsu Kohei;Shiga Daisuke;Kanda Tatsuhiko;Miyazaki Satoru;Kitamura Miho;Horiba Koji;Kumigashira Hiroshi
在~ 150 K的宽温度范围内，在~ 450 K处表现出独特的金属-绝缘体转变（MIT）。这种广泛的MIT伴随着晶格变形，与大多数其他过渡金属氧化物中观察到的尖锐MIT不同。一个长期存在的问题是确定电子-电子相关性在电子结构和MIT中的作用。然而，由于缺乏有关的能带结构的信息，阻碍了调查其不寻常的物理性质的起源。在这里，我们报告的电子能带结构的“绝缘”薄膜与轻微的空穴掺杂的角度分辨光电子能谱（ARPES）。ARPES显示出清晰的能带分散在单晶外延膜的表面。实验获得的能带结构进行了比较，基于密度泛函理论（DFT）与广义梯度近似+校正的能带结构计算结果。得到的能带结构与的密度泛函计算结果非常一致，表明电子-电子相关性在的电子结构中起着重要作用。此外，对不同的量子点的详细分析表明，特征MIT的起源是由于晶格变形引起的费米面变化引起的半金属-半金属或半金属-半导体转变。
exhibits a unique metal-insulator transition (MIT) at ∼450 K over a wide temperature range of ∼150 K. This broad MIT accompanied by lattice deformation differs from the sharp MITs observed in most other transition-metal oxides. A longstanding issue is determining the role of electron-electron correlation in the electronic structure and MIT of. However, the lack of information about the band structure ofhas hindered investigating the origin of its unusual physical properties. Here, we report the electronic band structure of “insulating”films with slight hole doping by angle-resolved photoemission spectroscopy (ARPES). ARPES showed clear band dispersion on the surface of single-crystalline epitaxial films. The experimentally obtained band structures were compared with band-structure calculation results based on density functional theory (DFT) with generalized gradient approximation +correction. The obtained band structures are in good agreement with the DFT calculations at, suggesting that electron-electron correlation plays an important role in the electronic structure of. Furthermore, the detailed analyses with varyingsuggest that the origin of the characteristic MIT inis a semimetal-semimetal or semimetal-semiconductor transition caused by changes in the Fermi surface due to lattice deformation.