Related papers: Two and one-dimensional honeycomb structures of si…
Materials with Dirac point are so amazing since the charge carriers are massless and have an effective speed of light. Among the reported two-dimensional silicon allotropes, no one showing such exciting nature was proved experimentally.…
2D materials can host interesting physics and have important applications in various fields. Recent experiment shows that monolayer PtSe$_2$ nanoflakes with neutral zigzag edges are stable. Here, we study semiconducting stoichiometric…
We have developed an unifying tight-binding Hamiltonian that can account for the electronic properties of recently proposed Si-based nanostructures, namely, Si graphene-like sheets and Si nanotubes. We considered the $sp^3s^*$ and $sp^{3}$…
The interesting properties of Kagome bands, consisting of Dirac bands and a flat band, have attracted extensive attention. However, the materials with only one Kagome band around the Fermi level cannot possess physical properties of Dirac…
Using ab-initio calculations, we study the electronic structure of gallium-doped germanium, which was found recently to be a superconductor, with a critical temperature of 0.5 Kelvins, and a particularly low density of Cooper pairs. The…
Buried-channel semiconductor heterostructures are an archetype material platform to fabricate gated semiconductor quantum devices. Sharp confinement potential is obtained by positioning the channel near the surface, however nearby surface…
We report first-principles results on the electronic structure of various silicene structures. For planar and simply buckled silicenes, we confirm their zero-gap nature and show a significant renormalization of their Fermi velocity by…
The electronic structure, specific heat, and thermal conductivity of silicon embedded in a monolayer graphene nanosheet are studied using Density Functional Theory. Two different shapes of the substitutional Si doping in the graphene are…
A new kind of three-dimensional carbon allotropes, termed carbon honeycomb (CHC), has recently been synthesized [PRL 116, 055501 (2016)]. Based on the experimental results, a family of graphene networks are constructed, and their electronic…
We study the electronic band structure and optical conductivity of an array of tunnel-coupled array of graphene nanoribbons. We show that due to the coupling of electronic edge states for the zigzag nanoribbon structure, the Fermi surface…
In this paper we study the electronic properties of carbon nanocones with one and two nappes, with pentagonal and heptagonal defects in their lattices. We use the continuum model, which is based on a Dirac-like Hamiltonian with the…
The elemental two-dimensional (2D) materials such as graphene, silicene, germanene, and black phosphorus have attracted considerable attention due to their fascinating physical properties. Structurally they possess the honeycomb or…
Using first principle calculations, we study the structural, optical and electronic properties of two-dimensional silicene-like structures of CSi7 (carbosilicene) and GeSi7 (germasilicene) monolayers. We show that both CSi7 and GeSi7…
We present ab initio calculations which show that the direct-band-gap, effective masses and Fermi velocities of charge carriers in ZnO monolayer (ML-ZnO) in graphene-like honeycomb structure are all tunable by application of in-plane…
Boron nitride structures have excellent thermal and chemical stabilities. Based on state-of-art theoretical calculations, we propose a wide gap semiconducting BN crystal with a three-dimensional hyperhoneycomb structure (Hp-BN), which is…
Two novel three-dimensional (3D) crystal structures of carbon (C) and germanium carbide (GeC2) were predicted using first-principles density-functional theory (DFT) calculations. These newly discovered 3D carbon allotrope and GeC2 are in…
Low-dimensional Si-based semiconductors are unique materials that can both match well with the Si-based electronics and satisfy the demand of miniaturization in modern industry. Owing to the lack of such materials, many researchers put…
After the discovery of Dirac fermions in graphene, it has become a natural question to ask whether it is possible to realize Dirac fermions in other two-dimensional (2D) materials as well. In this work, we report the discovery of multiple…
Silicon nanotube is constructed by rolling up a silicene, i.e., a monolayer of silicon atoms forming a two-dimensional honeycomb lattice. It is a semiconductor or an insulator owing to relatively large spin-orbit interactions induced by its…
We present an atomic-resolution observation and analysis of graphene constrictions and ribbons with sub-nanometer width. Graphene membranes are studied by imaging side spherical aberration-corrected transmission electron microscopy at 80…