Tunable spin helical Dirac quasiparticles on the surface of three-dimensional HgTe

Article

关键词: AUGMENTED-WAVE METHOD;    TOPOLOGICAL INSULATORS;    ENERGY-DEPENDENCE;    BAND-STRUCTURE;    QUANTUM-WELLS;    PHASE;    SEMICONDUCTOR;    HGSE;    PSEUDOPOTENTIALS;    1ST-PRINCIPLES;   

DOI  :  10.1103/PhysRevB.92.115436

来源: SCIE

【 摘 要 】

We show with systematic photoemission spectroscopy and scanning tunneling spectroscopy data that a spin helical surface state appears on the (110) surface of noncentrosymmetric, three-dimensional HgTe. The topological surface state in HgTe exhibits sharp, linear dispersion without k(z) variation, as well as clear, left-right imbalanced spin polarization and circular dichroism. Chemical gating by alkali metal deposition on the surface causes the unexpected opening and/or increase of a surface insulating gap without changing its topological property. Such an unusual behavior we uncover in three-dimensional HgTe sheds light on a convenient control of the Fermi surface and quantum transport in a topological insulator.

【 授权许可】

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