Three-dimensional Fermi surface and electron-phonon coupling in semimetallic 1T - TiTe2 studied by angle-resolved photoemission spectroscopy
Three-dimensional Fermi surface and electron-phonon coupling in semimetallic 1T - TiTe2 studied by angle-resolved photoemission spectroscopy
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DOI：
10.1103/physrevb.99.125112
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发表时间：
2018-08
影响因子：
3.7
通讯作者：
Xiao-Fang Tang;Xiao-Fang Tang;Xiao-Fang Tang;Yu-Xia Duan;Fan Wu;Shu-Yu Liu;Chen Zhang;Yin-Zou Zhao;J. Song;Yang Luo;Qi-Yi Wu;Jun He;H. Liu;Wen Xu;Wen Xu;Jianqiao Meng;Jianqiao Meng
中科院分区：
文献类型：
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作者：
Xiao-Fang Tang;Xiao-Fang Tang;Xiao-Fang Tang;Yu-Xia Duan;Fan Wu;Shu-Yu Liu;Chen Zhang;Yin-Zou Zhao;J. Song;Yang Luo;Qi-Yi Wu;Jun He;H. Liu;Wen Xu;Wen Xu;Jianqiao Meng;Jianqiao Meng
我们利用可调谐光子能量激发的高分辨率角分辨光谱学研究了$1T\text{\ensuremath{-}}{\ mathm {TiTe}}_{2}$单晶的电子结构。观察和研究了典型的半金属类电子结构，其中载流子填充了与$\ mathm {Te}\phantom{\rule{0.28em}{0ex}}5p$带相关的多个空穴口袋和与Ti $3d$带相关的单电子口袋。结果表明：(1)Ti $ 3D $和$\ mathm {Te}\phantom{\rule{0.28em}{0ex}}5p$态具有明显的$1T\text{\ensuremath{-}}{\ mathm {TiTe}}_{2}$的三维电子带结构，具有典型的半金属特征；（ii）多重费米面片和复杂能带结构；(3)在费米能量以下约18 meV处色散存在明显的扭结，这是对$1T\text{\ensuremath{-}}{\ mathm {TiTe}}_{2}$单晶扭结结构的实验观察。我们发现这种扭结是由材料中的电子-声子耦合引起的。这些重要而有意义的发现可以帮助我们深入了解半金属$1T\text{\ensuremath{-}}{\ mathm {TiTe}}_{2}$的三维电子结构。
We present an investigation of the electronic structure of $1T\text{\ensuremath{-}}{\mathrm{TiTe}}_{2}$ single crystals using high-resolution angle-resolved photoemission spectroscopy utilizing tunable photon energy excitation. The typical semimetal-like electronic structure is observed and examined, where multiple hole pockets related to $\mathrm{Te}\phantom{\rule{0.28em}{0ex}}5p$ bands and one-electron pockets related to Ti $3d$ bands are populated by carriers. The obtained results reveal (i) a pronounced three-dimensional (3D) electronic band structure of $1T\text{\ensuremath{-}}{\mathrm{TiTe}}_{2}$ with typical semi-metallic features for both the Ti $3d$ and the $\mathrm{Te}\phantom{\rule{0.28em}{0ex}}5p$ states; (ii) multiple Fermi surface sheets and complex band structure; and (iii) an obvious kink in the dispersion at an energy of about 18 meV below the Fermi energy, which is an experimental observation of the kink structure in $1T\text{\ensuremath{-}}{\mathrm{TiTe}}_{2}$ single crystal. We find that this kink is induced by electron-phonon coupling in the material. These important and significant findings can help us to gain an in-depth understanding of the 3D electronic structure of semimetallic $1T\text{\ensuremath{-}}{\mathrm{TiTe}}_{2}$.