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Scanning tunneling microscopy on cleaved Mn₃Sn(0001) surface.

ABSTRACT: We have studied in-situ cleaved (0001) surfaces of the magnetic Weyl semimetal Mn₃Sn by low-temperature scanning tunneling microscopy and spectroscopy (STM/S). It was found that freshly cleaved Mn₃Sn surfaces are covered with unknown clusters, and the application of voltage pulses in the tunneling condition was needed to achieve atomically flat surfaces. STM topographs taken on the flat terrace show a bulk-terminated 1?×?1 honeycomb lattice with the Sn site brightest. First-principles calculations reveal that the brightest contrast at the Sn site originates from the surrounding surface Mn d orbitals. Tunneling spectroscopy performed on the as-cleaved and voltage-pulsed surfaces show a prominent semimetal valley near the Fermi energy.

SUBMITTER: Yang HH

PROVIDER: S-EPMC6609646 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature

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Scanning tunneling microscopy on cleaved Mn3Sn(0001) surface.

Yang Hung-Hsiang HH Lee Chi-Cheng CC Yoshida Yasuo Y Ikhlas Muhammad M Tomita Takahiro T Nugroho Agustinus A Ozaki Taisuke T Nakatsuji Satoru S Hasegawa Yukio Y

Scientific reports 20190704 1

We have studied in-situ cleaved (0001) surfaces of the magnetic Weyl semimetal Mn3Sn by low-temperature scanning tunneling microscopy and spectroscopy (STM/S). It was found that freshly cleaved Mn3Sn surfaces are covered with unknown clusters, and the application of voltage pulses in the tunneling condition was needed to achieve atomically flat surfaces. STM topographs taken on the flat terrace show a bulk-terminated 1 × 1 honeycomb lattice with the Sn site brightest. First ...[more]

PMID: 31273260

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