Electronic and spin structure of the wide-band-gap topological insulator: Nearly stoichiometric Bi2Te2S

Article

关键词: SINGLE DIRAC CONE;    EXPERIMENTAL REALIZATION;    TETRADYMITE;    SYSTEM;    TE;    SE;   

DOI  :  10.1103/PhysRevB.97.205113

来源: SCIE

【 摘 要 】

We have grown the phase-homogeneous ternary compound with composition Bi2Te1.85S1.15 very close to the stoichiometric Bi2Te2S. The measurements performed with spin-and angle-resolved photoelectron spectroscopy as well as density functional theory andGW calculations revealed awide-band-gap three-dimensional topological insulator phase. The surface electronic spectrum is characterized by the topological surface state (TSS) with Dirac point located above the valence band and Fermi level lying in the band gap. TSS band dispersion and constant energy contour manifest a weak warping effect near the Fermi level along with in-plane and out-of-plane spin polarization along the (Gamma) over bar-(K) over bar line. We identified four additional states at deeper binding energies with high in-plane spin polarization.

【 授权许可】

Free