Imaging electronic states on topological semimetals using scanning tunneling microscopy
Abstract
Following the intense studies on topological insulators, significant efforts have recently been devoted to the search for gapless topological systems. These materials not only broaden the topological classification of matter but also provide a condensed matter realization of various relativistic particles and phenomena previously discussed mainly in high energy physics. Weyl semimetals host massless, chiral, low-energy excitations in the bulk electronic band structure, whereas a symmetry protected pair of Weyl fermions gives rise to massless Dirac fermions. We employed scanning tunneling microscopy/spectroscopy to explore the behavior of electronic states both on the surface and in the bulk of topological semimetal phases. By mapping the quasiparticle interference and emerging Landau levels at high magnetic field in Dirac semimetals CdAs and NaBi, we observed extended Dirac-like bulk electronic bands. Quasiparticle interference imaged on Weyl semimetal TaAs demonstrated the predicted momentum dependent delocalization of Fermi arc surface states in the vicinity of the surface-projected Weyl nodes.
Keywords
Cite
@article{arxiv.1610.07197,
title = {Imaging electronic states on topological semimetals using scanning tunneling microscopy},
author = {Andras Gyenis and Hiroyuki Inoue and Sangjun Jeon and Brian B. Zhou and Benjamin E. Feldman and Zhijun Wang and Jian Li and Shan Jiang and Quinn D. Gibson and Satya K. Kushwaha and Jason W. Krizan and Ni Ni and Robert J. Cava and B. Andrei Bernevig and Ali Yazdani},
journal= {arXiv preprint arXiv:1610.07197},
year = {2016}
}