Prediction of flatness-driven quantum spin Hall effect in functionalized germanene and stanene

文献情報

出版日 2016-09-21

DOI 10.1039/C6CP06216D

インパクトファクター 3.676

著者

Run-wu Zhang, Wei-xiao Ji, Chang-wen Zhang, Ping Li, Pei-ji Wang

原文を見る

要旨

Searching for realistic materials able to realize room-temperature quantum spin Hall (QSH) effects is currently a growing field, especially when compatibility with the current group-IV electronics industry is required. Here we predict, through first-principles calculations, a new class of QSH phases in flattened germanene and stanene functionalized with X atoms (f-GeX2 and f-SnX2; X = H, F, Cl, Br, I) with a bulk gap as large as 0.56 eV, that can be tuned efficiently under mechanical strain. More interestingly, different from the normal band order in buckled germanane and stanane, the structural flatness leads to an inverted band order without spin–orbit coupling (SOC), whereas the SOC only opens the band gap. We also find that the characteristics of edge states, such as the Fermi velocity, are enhanced greatly by edge modification. When these films are deposited on a BN substrate, a nontrivial QSH state is preserved with a Dirac cone lying within the nontrivial band gap. These findings provide a promising platform for future realistic applications of the QSH effect at room temperature in two-dimensional group-IV films.

掲載誌

Physical Chemistry Chemical Physics

CiteScore: 5.5

自己引用率: 10.3%

年間論文数: 3036

Physical Chemistry Chemical Physics (PCCP) is an international journal co-owned by 19 physical chemistry and physics societies from around the world. This journal publishes original, cutting-edge research in physical chemistry, chemical physics and biophysical chemistry. To be suitable for publication in PCCP, articles must include significant innovation and/or insight into physical chemistry; this is the most important criterion that reviewers and Editors will judge against when evaluating submissions. The journal has a broad scope and welcomes contributions spanning experiment, theory, computation and data science. Topical coverage includes spectroscopy, dynamics, kinetics, statistical mechanics, thermodynamics, electrochemistry, catalysis, surface science, quantum mechanics, quantum computing and machine learning. Interdisciplinary research areas such as polymers and soft matter, materials, nanoscience, energy, surfaces/interfaces, and biophysical chemistry are welcomed if they demonstrate significant innovation and/or insight into physical chemistry. Joined experimental/theoretical studies are particularly appreciated when complementary and based on up-to-date approaches.