TY - JOUR
T1 - Spin-orbit coupling-induced band inversion and spin Chern insulator phase in plumbene and stanene
AU - Lee, Kyu Won
AU - Lee, Cheol Eui
N1 - Funding Information:
This work was supported by the National Research Foundation of Korea (Project No. 2019R1A2C1002076 ).
PY - 2020/3
Y1 - 2020/3
N2 - Z2 topology in two-dimensional group IVA materials has been explained by the band orders due to the crystal field splitting at the Γ point in the Brillouin zone, while spin-orbit coupling (SOC) was considered just to open a band gap. By using a multi-orbital tight-binding model, we show that the SOC induces band inversion between the conduction and valence bands at the Γ point in plumbene, which also is the case in stanene when the SOC strength increases. As a result of the band inversion, plumbene becomes a spin Chern insulator with a spin Chern number CS = 2 and, as the SOC strength increases, stanene undergoes a topological phase transition from a Z2 topological insulator to a spin Chern insulator with CS = 2. Under a staggered AB-sublattice potential, plumbene undergoes a phase transition from the spin Chern insulator with CS = 2 to a Z2 topological insulator with CS = 1.
AB - Z2 topology in two-dimensional group IVA materials has been explained by the band orders due to the crystal field splitting at the Γ point in the Brillouin zone, while spin-orbit coupling (SOC) was considered just to open a band gap. By using a multi-orbital tight-binding model, we show that the SOC induces band inversion between the conduction and valence bands at the Γ point in plumbene, which also is the case in stanene when the SOC strength increases. As a result of the band inversion, plumbene becomes a spin Chern insulator with a spin Chern number CS = 2 and, as the SOC strength increases, stanene undergoes a topological phase transition from a Z2 topological insulator to a spin Chern insulator with CS = 2. Under a staggered AB-sublattice potential, plumbene undergoes a phase transition from the spin Chern insulator with CS = 2 to a Z2 topological insulator with CS = 1.
KW - Band inversion
KW - Plumbene
KW - Spin Chern insulator
KW - Stanene
KW - Z topology
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U2 - 10.1016/j.cap.2019.12.009
DO - 10.1016/j.cap.2019.12.009
M3 - Article
AN - SCOPUS:85077370320
VL - 20
SP - 413
EP - 418
JO - Current Applied Physics
JF - Current Applied Physics
SN - 1567-1739
IS - 3
ER -