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Evidence for in-gap surface states on the single phase SmB₆(001) surface.

ABSTRACT: Structural and electronic properties of the SmB₆(001) single-crystal surface prepared by Ar⁺ ion sputtering and controlled annealing are investigated by scanning tunneling microscopy. In contrast to the cases of cleaved surfaces, we observe a single phase surface with a non-reconstructed p(1?×?1) lattice on the entire surface at an optimized annealing temperature. The surface is identified as Sm-terminated on the basis of spectroscopic measurements. On a structurally uniform surface, the emergence of the in-gap state, a robust surface state against structural variation, is further confirmed inside a Kondo hybridization gap at 4.4?K by temperature and atomically-resolved spatial dependences of the differential conductance spectrum near the Fermi energy.

SUBMITTER: Miyamachi T

PROVIDER: S-EPMC5634509 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature

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Evidence for in-gap surface states on the single phase SmB6(001) surface.

Miyamachi Toshio T Suga Shigemasa S Ellguth Martin M Tusche Christian C Schneider Claus M CM Iga Fumitoshi F Komori Fumio F

Scientific reports 20171009 1

Structural and electronic properties of the SmB6(001) single-crystal surface prepared by Ar+ ion sputtering and controlled annealing are investigated by scanning tunneling microscopy. In contrast to the cases of cleaved surfaces, we observe a single phase surface with a non-reconstructed p(1 × 1) lattice on the entire surface at an optimized annealing temperature. The surface is identified as Sm-terminated on the basis of spectroscopic measurements. On a structurally unifor ...[more]

PMID: 28993642

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