| AVS 63rd International Symposium & Exhibition | |
| Surface Science | Wednesday Sessions |
| Session SS+2D-WeM |
| Session: | Synthesis, Characterization, and Surface Science of Novel Materials and Interfaces |
| Presenter: | Weimin Zhou, University of California - Riverside |
| Authors: | W. Zhou, University of California - Riverside H. Zhu, University of California - Riverside J.A. Yarmoff, University of California - Riverside |
| Correspondent: | Click to Email |
Bismuth selenide (Bi2Se3) and isolated bilayers of bismuth both behave as topological insulators, which are two-dimensional materials that conduct along the surface through topological surface states (TSS). These materials show great promise for use in spintronics and quantum computation. Because the TSS are located at the surface, it is important to understand the relationships between the surface atomic and electronic structures. Low energy ion scattering (LEIS) is a simple, but powerful surface sensitive technique that is ideal for structural analysis. LEIS, using Na+ projectiles, is employed here in two distinct modes. First, time-of-flight (TOF) spectra are collected using low index incidence directions. This allows for a direct measure of the surface termination with minimal beam damage. Second, impact collision ion scattering spectroscopy (ICISS), which involves the collection of angular distributions using a large scattering angle, is employed to study the structure of the outermost few atomic layers. This work investigates the surfaces of clean Se-terminated Bi2Se3 and after a Bi bilayer has been grown on top by molecular beam epitaxy (MBE). Molecular dynamics (MD) simulations of ICISS are compared to the experimental data in order to ascertain the surface structures.