RUTGERS CONDENSED MATTER SEMINARSRUTGERS COLLOQUIUM

Nanoscale Band Structure Imaging of Topological Materials: Sb and SmB6

Jennifer Hoffman
Harvard

Abstract

We use STM to study the topological semimetal Sb(111), and report the first simultaneous observation and quantitative reconciliation of Landau level spectroscopy and quasiparticle interference imaging on any material. We thus establish the technique of band structure tunneling microscopy (BSTM), and use it to reconstruct the multi-component surface states band structure of Sb with nanoscale spatial resolution, and to quantify essential metrics for spintronics applications. We also conduct the first atomic resolution spectroscopic study of the proposed topological Kondo insulator SmB6. We disentangle the tunneling interference between two distinct bands, to reveal a robust hybridization gap which universally spans the Fermi level on four distinct surface morphologies, paving the way for more detailed understanding of the purported topological surface states.