We show that in the new topological-insulator compound Bi_{1.5}Sb_{0.5}Te_{1.7}Se_{1.3} one can achieve a surfaced-dominated transport where the surface channel contributes up to 70% of the total conductance. Furthermore, it was found that in this material the transport properties sharply reflect the time dependence of the surface chemical potential, presenting a sign change in the Hall coefficient with time. We demonstrate that such an evolution makes us observe both Dirac holes and electrons on the surface, which allows us to reconstruct the surface band dispersion across the Dirac point.
@article{arxiv.1105.5483,
title = {Observation of Dirac Holes and Electrons in a Topological Insulator},
author = {A. A. Taskin and Zhi Ren and Satoshi Sasaki and Kouji Segawa and Yoichi Ando},
journal= {arXiv preprint arXiv:1105.5483},
year = {2011}
}
Comments
4 pages, 4 figures, accepted for publication in PRL