title: Robust Room-Temperature Quantum Spin Hall Effect in Methyl-functionalized InBi honeycomb film.
abstract: Two-dimensional (2D) group-III-V honeycomb films have attracted significant interest for their potential application in fields of quantum computing and nanoelectronics. Searching for 2D III-V films with high structural stability and large-gap are crucial for the realizations of dissipationless transport edge states using quantum spin Hall (QSH) effect. Based on first-principles calculations, we predict that the methyl-functionalized InBi monolayer (InBiCH3) has no dynamic instability, and hosts QSH state with a band gap as large as 0.29 eV, exhibiting an interesting electronic behavior viable for room-temperature applications. The topological characteristic is confirmed by s-pxy band inversion, topological invariant Z2 number, and the time-reversal symmetry protected helical edge states. Noticeably, the QSH states are tunable and robust against the mechanical strain, electric field and different levels of methyl coverages. We also find that InBiCH3 supported on h-BN substrate maintains a nontrivial QSH state, which harbors the edge states lying within the band gap of substrate. These findings demonstrate that the methyl-functionalized III-V films may be a good QSH platform for device design and fabrication in spintronics.
authors.affiliation: School of Physics and Technology, University of Jinan, Jinan, Shandong, 250022, People's Republic of China.|School of Physics, State Key laboratory of Crystal Materials, Shandong University, Jinan, Shandong, 250100, People's Republic of China.
authors.forename: Sheng-Shi
authors.initials: SS
authors.lastname: Li
authors.affiliation: School of Physics and Technology, University of Jinan, Jinan, Shandong, 250022, People's Republic of China.
authors.forename: Wei-Xiao
authors.initials: WX
authors.lastname: Ji
authors.affiliation: School of Physics and Technology, University of Jinan, Jinan, Shandong, 250022, People's Republic of China.
authors.forename: Chang-Wen
authors.initials: CW
authors.lastname: Zhang
authors.affiliation: School of Physics, State Key laboratory of Crystal Materials, Shandong University, Jinan, Shandong, 250100, People's Republic of China.
authors.forename: Shu-Jun
authors.initials: SJ
authors.lastname: Hu
authors.affiliation: School of Physics and Technology, University of Jinan, Jinan, Shandong, 250022, People's Republic of China.
authors.forename: Ping
authors.initials: P
authors.lastname: Li
authors.affiliation: School of Physics and Technology, University of Jinan, Jinan, Shandong, 250022, People's Republic of China.
authors.forename: Pei-Ji
authors.initials: PJ
authors.lastname: Wang
authors.affiliation: School of Physics and Technology, University of Jinan, Jinan, Shandong, 250022, People's Republic of China.
authors.forename: Bao-Min
authors.initials: BM
authors.lastname: Zhang
authors.affiliation: School of Physics and Technology, University of Jinan, Jinan, Shandong, 250022, People's Republic of China.
authors.forename: Chong-Long
authors.initials: CL
authors.lastname: Cao