Shubnikov-de-Haas oscillations were studied under high magnetic field in Bi2Se3 nanostructures grown by Chemical Vapor Transport, for different bulk carrier densities ranging from 3×1019cm−3 to 6×1017cm−3. The contribution of topological surface states to electrical transport can be identified and separated from bulk carriers and massive two-dimensional electron gas. Band bending is investigated, and a crossover from upward to downward band bending is found at low bulk density, as a result of a competition between bulk and interface doping. These results highlight the need to control electrical doping both in the bulk and at interfaces in order to study only topological surface states.
@article{arxiv.1508.01881,
title = {Band bending inversion in Bi$_2$Se$_3$ nanostructures},
author = {Louis Veyrat and Fabrice Iacovella and Joseph Dufouleur and Christian Nowka and Hannes Funke and Ming Yang and Walter Escoffier and Michel Goiran and Bernd Buechner and Silke Hampel and Romain Giraud},
journal= {arXiv preprint arXiv:1508.01881},
year = {2015}
}