Observation of oscillatory relaxation in the Sn-terminated surface of epitaxial rock-salt SnSe $\{111\}$ topological crystalline insulator

Abstract

Topological crystalline insulators have been recently predicted and observed in rock-salt structure SnSe $\{111\}$ thin films. Previous studies have suggested that the Se-terminated surface of this thin film with hydrogen passivation, has a reduced surface energy and is thus a preferred configuration. In this paper, synchrotron-based angle-resolved photoemission spectroscopy, along with density functional theory calculations, are used to demonstrate conclusively that a rock-salt SnSe $\{111\}$ thin film epitaxially-grown on \ce{Bi2Se3} has a stable Sn-terminated surface. These observations are supported by low energy electron diffraction (LEED) intensity-voltage measurements and dynamical LEED calculations, which further show that the Sn-terminated SnSe $\{111\}$ thin film has undergone a surface structural relaxation of the interlayer spacing between the Sn and Se atomic planes. In sharp contrast to the Se-terminated counterpart, the observed Dirac surface state in the Sn-terminated SnSe $\{111\}$ thin film is shown to yield a high Fermi velocity, $0.50\times 10^6$m/s, which suggests a potential mechanism of engineering the Dirac surface state of topological materials by tuning the surface configuration.

arXiv comment12 pages, 13 figures, supplementary materials included

References in corpus (26)

• Topological Insulators
• Topological insulators and superconductors
• Maximally-localized generalized Wannier functions for composite energy bands
• Wannier90: A Tool for Obtaining Maximally-Localised Wannier Functions
• Classification of topological insulators and superconductors in three spatial dimensions
• Maximally-localized Wannier functions for entangled energy bands
• Topological Crystalline Insulators
• Topological Crystalline Insulators in the SnTe Material Class
• Experimental realization of a topological crystalline insulator in SnTe
• Topological crystalline insulator states in Pb(1-x)Sn(x)Se
• A topological crystalline insulator (TCI) phase via topological phase transition and crystalline mirror symmetry
• Antiferromagnetic topological insulators
• Surface States of Topological Crystalline Insulators in IV-VI Semiconductors
• Tunability of the k-space Location of the Dirac Cones in the Topological Crystalline Insulator Pb1-xSnxTe
• Rock-salt SnS and SnSe: Native Topological Crystalline Insulators
• Experimental observation of Dirac-like surface states and topological phase transition in Pb${}_{1-x}$Sn${}_x$Te(111) films
• Two types of Dirac-cone surface states on (111) surface of topological crystalline insulator SnTe
• The topological-crystalline-insulator (Pb,Sn)Te - surface states and their spin-polarization
• Band structure of SnTe studied by Photoemission Spectroscopy
• Observation of topological crystalline insulator surface states on (111)-oriented Pb${}_{1-x}$Sn${}_x$Se films
• Quasiparticle Interference on the Surface of Topological Crystalline Insulator Pb(1-x)Sn(x)Se
• SU(3) Quantum Hall Ferromagnetism in SnTe
• $(111)$ surface states of SnTe
• Observation of surface states on heavily indium doped SnTe(111), a superconducting topological crystalline insulator
• Sudden gap-closure across the topological phase transition in Bi${}_{2-x}$In${}_x$Se${}_3$
• ARPES study of the epitaxially grown topological crystalline insulator SnTe(111)

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