Simultaneous Quantization of Bulk Conduction and Valence States through Adsorption of Nonmagnetic Impurities on Bi2Se3
Simultaneous Quantization of Bulk Conduction and Valence States through Adsorption of Nonmagnetic Impurities on Bi2Se3
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DOI：
10.1103/physrevlett.107.086802
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发表时间：
2011-08-16
影响因子：
8.6
通讯作者：
Hofmann, Philip
中科院分区：
文献类型：
--
作者：
Bianchi, Marco;Hatch, Richard C.;Hofmann, Philip
将拓扑绝缘体Bi2Se3的（111）表面暴露于一氧化碳导致在角分辨光电发射中观察到的特征的强烈移位。该行为非常类似于经常报道的表面的“老化”效应，并且可以得出结论，这种老化最有可能是由于剩余气体分子的吸附。光谱变化也类似于最近报道的磁性吸附原子Fe的吸附。所有的光谱变化可以解释的导带和价带状态的同时限制。这仅仅是因为Bi2Se3不寻常的体电子结构。价带量子化导致的光谱特征类似于那些在狄拉克点的带隙开口。
Exposing the (111) surface of the topological insulator Bi2Se3 to carbon monoxide results in strong shifts of the features observed in angle-resolved photoemission. The behavior is very similar to an often reported "aging'' effect of the surface, and it is concluded that this aging is most likely due to the adsorption of rest gas molecules. The spectral changes are also similar to those recently reported in connection with the adsorption of the magnetic adatom Fe. All spectral changes can be explained by a simultaneous confinement of the conduction band and valence band states. This is possible only because of the unusual bulk electronic structure of Bi2Se3. The valence band quantization leads to spectral features which resemble those of a band gap opening at the Dirac point.