A Helium-Surface Interaction Potential of Bi${}_2$Te${}_3$(111) from Ultrahigh-Resolution Spin-Echo Measurements

Abstract

We have determined an atom-surface interaction potential for the He$-$Bi${}_2$Te${}_3$(111) system by analysing ultrahigh resolution measurements of selective adsorption resonances. The experimental measurements were obtained using ${}^3$He spin-echo spectrometry. Following an initial free-particle model analysis, we use elastic close-coupling calculations to obtain a three-dimensional potential. The three-dimensional potential is then further refined based on the experimental data set, giving rise to an optimised potential which fully reproduces the experimental data. Based on this analysis, the He$-$Bi${}_2$Te${}_3$(111) interaction potential can be described by a corrugated Morse potential with a well depth $D=(6.22\pm 0.05)\mathrm{meV}$, a stiffness $\kappa =(0.92\pm 0.01){\mathring{\mathrm{A}}}^{-1}$ and a surface electronic corrugation of $(9.6\pm 0.2)$% of the lattice constant. The improved uncertainties of the atom-surface interaction potential should also enable the use in inelastic close-coupled calculations in order to eventually study the temperature dependence and the line width of selective adsorption resonances.

References in corpus (8)

• Topological Insulators
• Topological insulators and superconductors
• First observation of Spin-Momentum Helical Locking in Bi2Se3 and Bi2Te3, demonstration of Topological-Order at 300K and a realization of topological-transport-regime
• A topological insulator surface under strong Coulomb, magnetic and disorder perturbations
• Bulk Band Structure of Bi${}_2$Te${}_3$
• Electron-Phonon Coupling and Surface Debye Temperature of Bi${}_2$Te${}_3$(111) from Helium Atom Scattering
• Robust gapless surface state and Rashba-splitting bands upon surface deposition of magnetic Cr on Bi${}_2$Se${}_3$
• Anomalous behavior in the phonon dispersion of the (001) surface of Bi${}_2$Te${}_3$ determined from helium atom-surface scattering measurements

Cited by in corpus (2)

• Origin of the Electron-Phonon Interaction of Topological Semimetal Surfaces Measured with Helium Atom Scattering
• A fully ab initio approach to inelastic atom-surface scattering