In this report, we scrutinize the thickness dependent resistivity data from the recent literature on electrical transport measurements in topological insulators. A linear increase in resistivity with increase in thickness is expected in the case of these materials since they have an insulating bulk and conducting surface. However, such a trend is not seen in the resistivity versus thickness data for all the cases examined, except for some samples, where it holds for a narrow range of thickness.
@article{arxiv.1304.4037,
title = {Many Topological Insulators Fail the Surface Conduction Test},
author = {Sourabh Barua and K. P. Rajeev},
journal= {arXiv preprint arXiv:1304.4037},
year = {2014}
}