相关论文: Decoupling Graphene from SiC(0001) via Oxidation
The 5x5, 6rt(3)x6rt(3)-R30deg, and graphene-covered 6rt(3)x6rt(3)-R30deg reconstructions of the SiC(0001) surface are studied by scanning tunneling microscopy and spectroscopy. For the 5x5 structure a rich spectrum of surface states is…
Terrace-sized, single-orientation graphene can be grown on top of a carbon buffer layer on silicon carbide by thermal decomposition. Despite its homogeneous appearance, a surprisingly large variation in electron transport properties is…
The speed of silicon-based transistors has reached an impasse in the recent decade, primarily due to scaling techniques and the short-channel effect. Conversely, graphene (a revolutionary new material possessing an atomic thickness) has…
Epitaxial graphene on SiC possesses, quite remarkably, an electron spectrum similar to that of freestanding samples. Yet, the coupling to the substrate, albeit small, affects the quasiparticle properties. Combining \emph{ab initio}…
Graphene outstanding properties directly come from its pecular electronic structure and thus from the honeycomb lattice symmetry. The way interaction with the substrate impact this lattice is of primary importance. This is peculiarly true…
Graphene and few-layer graphene at high bias expose a wealth of phenomena due to the high temperatures reached. With in-situ transmission electron microscopy (TEM) we observe directly how the current modifies the structure, and vice versa.…
We address the stability of the surface phases that occur on the C-side of 3C-SiC($\bar{1} \bar{1} \bar{1}$) at the onset of graphene formation. In this growth range, experimental reports reveal a coexistence of several surface phases. This…
Controlling the type and density of charge carriers by doping is the key step for developing graphene electronics. However, direct doping of graphene is rather a challenge. Based on first-principles calculations, a concept of overcoming…
Following the identification of the pi bond in graphene, in this work, a pi bond constructed through side-to-side overlap of half-filled 6pz orbitals was observed in a non-carbon crystal of Pb1-xSnxSe (x=0.34) (PSS), a prototype topological…
The materials science of graphene grown epitaxially on the hexagonal basal planes of SiC crystals is reviewed. We show that the growth of epitaxial graphene on Si-terminated SiC(0001) is much different than growth on the C-terminated…
Ca-intercalation has opened a way for superconductivity in graphene on SiC. However, the atomic and electronic structures being critical for superconductivity are still under discussion. We find the essential role of the interface between…
We address the energetic stability of the graphene/SiC(0001) interface and the associated binding mechanism by studying a series of low-strain commensurate interface structures within a density functional scheme. Among the structures with…
The electronic properties of few-layer graphene grown on the carbon-face of silicon carbide (SiC) are found to be strongly dependent on the number of layers. The carrier mobility is larger in thicker graphene because substrate-related…
We have investigated the atomic structure of superconducting Ca-intercalated bilayer graphene on a SiC(0001) substrate using total-reflection high-energy positron diffraction. By comparing the experimental rocking-curves with ones…
Multi-layer graphene on the carbon face of silicon carbide is an intriguing electronic system which typically consists of a stack of ten or more layers. Rotational stacking faults in this system dramatically reduce inter-layer coherence. In…
We present a technique to tune the charge density of epitaxial graphene via an electrostatic gate that is buried in the silicon carbide substrate. The result is a device in which graphene remains accessible for further manipulation or…
We report that the $\pi$ band of graphene sensitively changes as a function of an external potential induced by Na especially when the potential becomes periodic at low temperature. We have measured the band structures from the graphene…
Single-crystalline transition metal films are ideal playing fields for the epitaxial growth of graphene and graphene-base materials. Graphene-silicon layered structures were successfully constructed on Ir(111) thin film on Si substrate with…
Our first-principles calculations show that an energy gap around 0.12-0.25 eV can be engineered in epitaxial graphene on SiC(0001) through the non-covalent intercalation of transition- or alkali-metals, yet originated from the distinct…
We determine conditions for the formation of compressible stripes near the quantum Hall effect (QHE) edges of top-gated epitaxial graphene on Si-terminated SiC (G/SiC) and compare those to graphene exfoliated onto insulating substrate in…