Topological insulators represent novel phases of quantum matter with an insulating bulk gap and gapless edges or surface states. The two-dimensional topological insulator phase was predicted in HgTe quantum wells and confirmed by transport measurements. Recently, Bi2Se3 and related materials have been proposed as three-dimensional topological insulators with a single Dirac cone on the surface and verified by angle-resolved photoemission spectroscopy experiments. Here, we show unambiguous transport evidence of topological surface states through periodic quantum interference effects in layered single-crystalline Bi2Se3 nanoribbons. Pronounced Aharonov-Bohm oscillations in the magnetoresistance clearly demonstrate the coverage of two-dimensional electrons on the entire surface, as expected from the topological nature of the surface states. The dominance of the primary h/e oscillation and its temperature dependence demonstrate the robustness of these electronic states. Our results suggest that topological insulator nanoribbons afford novel promising materials for future spintronic devices at room temperature.
@article{arxiv.0908.3314,
title = {Aharonov-Bohm interference in topological insulator nanoribbons},
author = {Hailin Peng and Keji Lai and Desheng Kong and Stefan Meister and Yulin Chen and Xiao-Liang Qi and Shou-Cheng Zhang and Zhi-Xun Shen and Yi Cui},
journal= {arXiv preprint arXiv:0908.3314},
year = {2015}
}