Non-trivial Surface States of Samarium Hexaboride at the (111) Surface

Overview

Journal Nat Commun

Specialty Biology

Date 2019 May 26

PMID 31127112

Citations 1

Authors

Yoshiyuki Ohtsubo

Yuki Yamashita

Kenta Hagiwara

Shin-Ichiro Ideta

Kiyohisa Tanaka

Ryu Yukawa

Koji Horiba

Hiroshi Kumigashira

Koji Miyamoto

Taichi Okuda

Wataru Hirano

Fumitoshi Iga

Shin-Ichi Kimura

Affiliations

Soon will be listed here.

Abstract

The peculiar metallic electronic states observed in the Kondo insulator, samarium hexaboride (SmB), has stimulated considerable attention among those studying non-trivial electronic phenomena. However, experimental studies of these states have led to controversial conclusions mainly due to the difficulty and inhomogeneity of the SmB crystal surface. Here, we show the detailed electronic structure of SmB with angle-resolved photoelectron spectroscopy measurements of the three-fold (111) surface where only two inequivalent time-reversal-invariant momenta (TRIM) exist. We observe the metallic two-dimensional state was dispersed across the bulk Kondo gap. Its helical in-plane spin polarisation around the surface TRIM indicates that SmB is topologically non-trivial, according to the topological classification theory for weakly correlated systems. Based on these results, we propose a simple picture of the controversial topological classification of SmB.

Citing Articles

Breakdown of bulk-projected isotropy in surface electronic states of topological Kondo insulator SmB(001).

Ohtsubo Y, Nakaya T, Nakamura T, Le Fevre P, Bertran F, Iga F Nat Commun. 2022; 13(1):5600.

PMID: 36151212 PMC: 9508144. DOI: 10.1038/s41467-022-33347-0.

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