Wenguang Zhu

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Using first-principles calculations within density functional theory, we explore the feasibility of converting ternary half-Heusler compounds into a new class of three-dimensional topological insulators (3DTI). We demonstrate that the electronic structure of unstrained LaPtBi as a prototype system exhibits a distinct band-inversion feature. The 3DTI phase(More)
Topological insulators are characterized by a non-trivial band topology driven by the spin-orbit coupling. To fully explore the fundamental science and application of topological insulators, material realization is indispensable. Here we predict, based on tight-binding modelling and first-principles calculations, that bilayers of perovskite-type(More)
"Noncompensated n-p codoping" is established as an enabling concept for enhancing the visible-light photoactivity of TiO2 by narrowing its band gap. The concept embodies two crucial ingredients: the electrostatic attraction within the n-p dopant pair enhances both the thermodynamic and kinetic solubilities, and the noncompensated nature ensures the creation(More)
Using first-principles calculations within density functional theory, we study the energetics and kinetics of C nucleation in the early stages of epitaxial graphene growth on three representative stepped metal surfaces: Ir(111), Ru(0001), and Cu(111). We find that on the flat surfaces of Ir(111) and Ru(0001), two C atoms repel each other, while they prefer(More)
Using first-principles calculations within density functional theory, we investigate the electronic and chemical properties of a single-layer MoS(2) adsorbed on Ir(111), Pd(111), or Ru(0001), three representative transition metal substrates having varying work functions but each with minimal lattice mismatch with the MoS(2) overlayer. We find that, for each(More)
We theoretically investigate the possibility of establishing ferromagnetism in the topological insulator Bi2Se3 via magnetic doping of 3d transition metal elements. The formation energies, charge states, band structures, and magnetic properties of doped Bi2Se3 are studied using first-principles calculations within density functional theory. Our results show(More)
Surface states--the electronic states emerging as a solid material terminates at a surface--are usually vulnerable to contaminations and defects. The robust topological surface state(s) (TSS) on the three-dimensional topological insulators provide a perfect platform for exploiting surface states in less stringent environments. Employing first-principles(More)
To fully exploit the device potential of graphene, reliable production of large-area, high-quality samples is required. Epitaxial growth on metal substrates have shown promise in this regard, but further improvement would be facilitated by a more complete understanding of the atomistic processes involved in the early growth stages. Using first-principles(More)
MoS2 on polycrystalline metal substrates emerges as an intriguing growth system compared to that on insulating substrates due to its direct application as an electrocatalyst in hydrogen evolution. However, the growth is still indistinct with regard to the effects of the inevitably evolved facets. Herein, we demonstrate for the first time that the(More)
Using first-principles total-energy calculations, we show that an adatom can easily climb up at monatomic-layer-high steps on several representative fcc metal (110) surfaces via a place exchange mechanism. Inclusion of such novel adatom ascending processes in kinetic Monte Carlo simulations of Al(110) homoepitaxy as a prototypical model system can lead to(More)