Research output: Contribution to journal › Article › peer-review
Geometric and electronic structure of the cs-doped Bi2Se3(0001) surface. / Otrokov, M. M.; Ernst, A.; Mohseni, K. et al.
In: Physical Review B, Vol. 95, No. 20, 205429, 22.05.2017.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - Geometric and electronic structure of the cs-doped Bi2Se3(0001) surface
AU - Otrokov, M. M.
AU - Ernst, A.
AU - Mohseni, K.
AU - Fulara, H.
AU - Roy, S.
AU - Castro, G. R.
AU - Rubio-Zuazo, J.
AU - Ryabishchenkova, A. G.
AU - Kokh, K. A.
AU - Tereshchenko, O. E.
AU - Aliev, Z. S.
AU - Babanly, M. B.
AU - Chulkov, E. V.
AU - Meyerheim, H. L.
AU - Parkin, S. S.P.
N1 - Publisher Copyright: © 2017 American Physical Society
PY - 2017/5/22
Y1 - 2017/5/22
N2 - Using surface x-ray diffraction and scanning tunneling microscopy in combination with first-principles calculations, we have studied the geometric and electronic structure of Cs-deposited Bi2Se3(0001) surface kept at room temperature. Two samples were investigated: a single Bi2Se3 crystal, whose surface was Ar sputtered and then annealed at ∼500◦C for several minutes prior to Cs deposition, and a 13-nm-thick epitaxial Bi2Se3 film that was not subject to sputtering and was annealed only at ∼350◦C. In the first case, a considerable fraction of Cs atoms occupy top layer Se atoms sites both on the terraces and along the upper step edges where they form one-dimensional-like structures parallel to the step. In the second case, Cs atoms occupy the fcc hollow site positions. First-principles calculations reveal that Cs atoms prefer to occupy Se positions on the Bi2Se3(0001) surface only if vacancies are present, which might be created during the crystal growth or during the surface preparation process. Otherwise, Cs atoms prefer to be located in fcc hollow sites in agreement with the experimental finding for the MBE-grown sample.
AB - Using surface x-ray diffraction and scanning tunneling microscopy in combination with first-principles calculations, we have studied the geometric and electronic structure of Cs-deposited Bi2Se3(0001) surface kept at room temperature. Two samples were investigated: a single Bi2Se3 crystal, whose surface was Ar sputtered and then annealed at ∼500◦C for several minutes prior to Cs deposition, and a 13-nm-thick epitaxial Bi2Se3 film that was not subject to sputtering and was annealed only at ∼350◦C. In the first case, a considerable fraction of Cs atoms occupy top layer Se atoms sites both on the terraces and along the upper step edges where they form one-dimensional-like structures parallel to the step. In the second case, Cs atoms occupy the fcc hollow site positions. First-principles calculations reveal that Cs atoms prefer to occupy Se positions on the Bi2Se3(0001) surface only if vacancies are present, which might be created during the crystal growth or during the surface preparation process. Otherwise, Cs atoms prefer to be located in fcc hollow sites in agreement with the experimental finding for the MBE-grown sample.
KW - SINGLE DIRAC CONE
KW - TOPOLOGICAL INSULATORS
KW - AB-INITIO
KW - INTERFACE
KW - BI2TE3
KW - GROWTH
KW - STATE
UR - http://www.scopus.com/inward/record.url?scp=85047432592&partnerID=8YFLogxK
U2 - 10.1103/PhysRevB.95.205429
DO - 10.1103/PhysRevB.95.205429
M3 - Article
AN - SCOPUS:85047432592
VL - 95
JO - Physical Review B
JF - Physical Review B
SN - 2469-9950
IS - 20
M1 - 205429
ER -
ID: 15989408