A Helium-Surface Interaction Potential of Bi2Te3(111) from Ultrahigh-Resolution Spin-Echo Measurements

We have determined an atom-surface interaction potential for the He–BiTe(111) system by analysing ultrahigh resolution measurements of selective adsorption resonances. The experimental measurements were obtained using He spin-echo spectrometry. Following an initial free-particle model analysis, we u...

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Detalles Bibliográficos
Autores: Tamtögl, A., Pusterhofer, M., Bremholm, M., Hedegaard, E. M. J., Iversen, B. B., Hofmann, P., Ellis, J., Allison, W., Miret-Artés, Salvador, Ernst, W.E.
Tipo de recurso: artículo
Estado:Versión enviada para evaluación y publicación
Fecha de publicación:2018
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/188675
Acceso en línea:http://hdl.handle.net/10261/188675
Access Level:acceso abierto
Palabra clave:Adsorption
Bound states
Atom scattering
Atom-surface interaction
Bi2Te3
Topological insulators
Descripción
Sumario:We have determined an atom-surface interaction potential for the He–BiTe(111) system by analysing ultrahigh resolution measurements of selective adsorption resonances. The experimental measurements were obtained using 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–BiTe(111) interaction potential can be described by a corrugated Morse potential with a well depth D=(6.22±0.05)meV, a stiffness κ=(0.92±0.01) Å−1 and a surface electronic corrugation of (9.6 ± 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.