Two-dimensional quantum spin Hall (QSH) insulators with reasonably wide band gaps are imperative for the development of various innovative technologies. Through systematic density functional calculations and tight-binding simulations, we found that stanene on {\alpha}-alumina surface may possess a sizeable topologically nontrivial band gap (~0.25 eV) at the {\Gamma} point. Furthermore, stanene is atomically bonded to but electronically decoupled from the substrate, providing high structural stability and isolated QSH states to a large extent. The underlying physical mechanism is rather general, and this finding may lead to the opening of a new vista for the exploration of QSH insulators for room temperature device applications.
@article{arxiv.1701.07526,
title = {Possibility of Realizing Quantum Spin Hall Effect at Room Temperature in Stanene/Al2O3(0001)},
author = {Hui Wang and S. T. Pi and J. Kim and Z. Wang and H. H. Fu and R. Q. Wu},
journal= {arXiv preprint arXiv:1701.07526},
year = {2018}
}