Shan Guan

Low-energy effective Hamiltonian for giant-gap quantum spin Hall insulators in honeycomb X -hydride/halide ( X = N-Bi ) monolayers

Using the tight-binding method in combination with first-principles calculations, we systematically derive a low-energy effective Hilbert subspace and Hamiltonian with spin-orbit coupling for two-dimensional hydrogenated and halogenated group-V monolayers. These materials are proposed to be giant-gap quantum spin Hall insulators with record huge bulk band gaps opened by the spin-orbit coupling at the Dirac points, e.g., from 0.74 to 1.08 eV in Bi\textit{X} (\textit{X} = H, F, Cl, and Br) monolayers. We find that the low-energy Hilbert subspace mainly consists of

Large-Gap Quantum Spin Hall Insulator in Single Layer Bismuth Monobromide Bi4Br4

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2D Electrides as Promising Anode Materials for Na-Ion Batteries from First-Principles Study

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Effects of strain on electronic and optic properties of holey two-dimensional C2N crystals

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Theoretical prediction of MoN2 monolayer as a high capacity electrode material for metal ion batteries

orbitals from the group-V elements, and the giant first-order effective intrinsic spin-orbit coupling is from the on-site spin-orbit interaction. These features are quite distinct from those of group-IV monolayers such as graphene and silicene. There, the relevant orbital is

Type-II nodal loops: Theory and material realization

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Electronic, Dielectric, and Plasmonic Properties of Two-Dimensional Electride Materials X2N (X=Ca, Sr): A First-Principles Study.

and the effective intrinsic spin-orbit coupling is from the next-nearest-neighbor spin-orbit interaction processes. These systems represent the first real 2D honeycomb lattice materials in which the low-energy physics is associated with

Blue Phosphorene Oxide: Strain-Tunable Quantum Phase Transitions and Novel 2D Emergent Fermions

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Nonsymmorphic-symmetry-protected hourglass Dirac loop, nodal line, and Dirac point in bulk and monolayer X3SiTe6 ( X = Ta, Nb)

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Two-dimensional spin-orbit Dirac point in monolayer HfGeTe

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