相关论文: Fractal-like star-mesh transformations using graph…
The observation of the anomalous quantum Hall effect in exfoliated graphene flakes triggered an explosion of interest in graphene. It was however not observed in high quality epitaxial graphene multilayers grown on silicon carbide…
The history of quantum Hall standards stretches several decades and mostly begins with the use of GaAs given that 2D electron systems exhibit interesting quantum phenomena. At the end 2000s, research in 2D materials like graphene became…
We explore the robust quantization of the Hall resistance in epitaxial graphene grown on Si-terminated SiC. Uniquely to this system, the dominance of quantum over classical capacitance in the charge transfer between the substrate and…
We introduce a new scheme to realize suspended, multi-terminal graphene structures that can be current annealed successfully to obtain uniform, very high quality devices. A key aspect is that the bulky metallic contacts are not connected…
In graphene, which is an atomic layer of crystalline carbon, two of the distinguishing properties of the material are the charge carriers two-dimensional and relativistic character. The first experimental evidence of the two-dimensional…
This letter reports the impact of surface morphology on the carrier transport and RF performance of graphene FETs formed on epitaxial graphene films synthesized on SiC substrates. Such graphene exhibits long terrace structures with widths…
Realizing graphene's promise as an atomically thin and tunable platform for fundamental studies and future applications in quantum transport requires the ability to electrostatically define the geometry of the structure and control the…
We discuss the quantum Hall effect on a single-layer graphene in the framework of noncommutative (NC) phase space. We find it induces a shift in the Hall resistivity. Furthermore, comparison with experimental data reveals an upper bound on…
We have studied the electronic properties of epitaxial graphene devices patterned in a meander shape with the length up to a few centimeters and the width of few tens of microns. These samples show a pronounced dependence of the resistance…
It is theoretically possible to combine several Hall bars in arrays to define new quantum standards with perfectly quantized resistance values. We have thus, for the first time, developed and fabricated novel Quantum Hall Array Resistance…
Graphene technology has made great strides since the material was isolated more than a decade ago. However, despite improvements in growth quality and numerous 'hero' devices, challenges of uniformity remain, restricting large-scale…
We present the first experimental evidence for the multifractality of a transport property at a topological phase transition. In particular, we show that conductance fluctuations display multifractality at the integer-quantum-Hall $\nu=1…
A novel electrochemical means to generate atomic hydrogen, simplifying the synthesis and controllability of graphane formation on graphene is presented. High quality, vacuum grown epitaxial graphene (EG) was used as starting material for…
We report observation of the fractional quantum Hall effect (FQHE) in high mobility multi-terminal graphene devices, fabricated on a single crystal boron nitride substrate. We observe an unexpected hierarchy in the emergent FQHE states that…
The recent observation of fractional quantum Hall effect in high mobility suspended graphene devices introduced a new direction in graphene physics, the field of electron-electron interaction dynamics. However, the technique used currently…
The puzzle of recently observed insulating phase of graphene at filling factor $\nu=0$ in high magnetic field quantum Hall (QH) experiments is investigated. We show that the magnetic field driven Peierls-type lattice distortion (due to the…
We investigate the low-temperature magneto-transport properties of monolayer epitaxial graphene films formed on the Si-face of semi-insulating 4H-SiC substrates by a high temperature sublimation process. A high-k top-gate on the epitaxial…
Quantum confinement endows two-dimensional (2D) layered materials with exceptional physics and novel properties compared to their bulk counterparts. Although certain two- and few-layer configurations of graphene have been realized and…
We report on magnetotransport measurements of multi-terminal suspended graphene devices. Fully developed integer quantum Hall states appear in magnetic fields as low as 2 T. At higher fields the formation of longitudinal resistance minima…
We have observed the well-kown quantum Hall effect (QHE) in epitaxial graphene grown on silicon carbide (SiC) by using, for the first time, only commercial NdFeB permanent magnets at low temperature. The relatively large and homogeneous…