Suppression of the Spectral Weight of Topological Surface States on the Nanoscale via Local Symmetry Breaking

Abstract

In topological crystalline insulators the topological conducting surface states are protected by crystal symmetry, in principle making it possible to pattern nanoscale insulating and conductive motifs solely by breaking local symmetries on an otherwise homogenous, single-phase material. We show using scanning tunneling microscopy/spectroscopy that defects that break local symmetry of SnTe suppress electron tunneling over an energy range as large as the bulk band gap, an order of magnitude larger than that produced globally via magnetic fields or uniform structural perturbations. Complementary ab initio calculations show how local symmetry breaking obstructs topological surface states as shown by a threefold reduction of the spectral weight of the topological surface states. The finding highlights the potential benefits of manipulating the surface morphology to create devices that take advantage of the unique properties of topological surface states and can operate at practical temperatures.

References in corpus (24)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• Topological Insulators
• Topological Crystalline Insulators
• Topological Crystalline Insulators in the SnTe Material Class
• Experimental realization of a topological crystalline insulator in SnTe
• A topological crystalline insulator (TCI) phase via topological phase transition and crystalline mirror symmetry
• The space group classification of topological band insulators
• STM imaging of electronic waves on the surface of Bi${}_2$Te${}_3$: topologically protected surface states and hexagonal warping effects
• Helical Metal Inside a Topological Band Insulator
• Spin-filtered Edge States with an Electrically Tunable Gap in a Two-Dimensional Topological Crystalline Insulator
• Observation of Dirac node formation and mass acquisition in a topological crystalline insulator
• Dirac mass generation from crystal symmetry breaking on the surfaces of topological crystalline insulators
• Strain Induced Ferroelectric Topological Insulator
• Symmetry breaking and Landau quantization in topological crystalline insulators
• Band structure of SnTe studied by Photoemission Spectroscopy
• Strain engineering Dirac surface states in heteroepitaxial topological crystalline insulator thin films
• The translational side of topological band insulators
• Synthesis of SnTe Nanoplates with {100} and {111} Surfaces
• Probing variations of the Rashba spin-orbit coupling at the nanometer scale
• Superconducting properties of the In substituted Topological Crystalline Insulator, SnTe
• Topological Crystalline Insulator Nanomembrane with Strain-Tunable Band Gap
• The role of double TiO2 layers at the interface of FeSe/SrTiO3 superconductors
• Quasiparticle scattering from topological crystalline insulator SnTe (001) surface states
• Observation of surface states on heavily indium doped SnTe(111), a superconducting topological crystalline insulator