相关论文: Ballistic transport of graphene pnp junctions with…

We have developed a process to fabricate suspended graphene devices with local bottom gates, and tested it by realizing electrostatically controlled pn junctions on a suspended graphene mono-layer nearly 2 micrometers long. Measurements as…

We have developed the combination of an etching and deposition technique that enables the fabrication of locally gated graphene nanostructures of arbitrary design. Employing this method, we have fabricated graphene nanoconstrictions with…

Herein we discuss the fabrication of ballistic suspended graphene nanostructures supplemented with local gating. Using in-situ current annealing, we show that exceptional high mobilities can be obtained in these devices. A detailed…

The peculiar nature of electron scattering in graphene is among many exciting theoretical predictions for the physical properties of this material. To investigate electron scattering properties in a graphene plane, we have created a…

Ballistic semiconductor structures have allowed the realization of optics-like phenomena in electronics, including magnetic focusing and lensing. An extension that appears unique to graphene is to use both n and p carrier types to create…

We have fabricated graphene devices with a top gate separated from the graphene layer by an air gap--a design which does not decrease the mobility of charge carriers under the gate. This gate is used to realise p-n-p structures where the…

We fabricate and investigate high quality graphene devices with contactless, suspended top gates, and demonstrate formation of graphene pnp junctions with tunable polarity and doping levels. The device resistance displays distinct…

Graphene is a 2-dimensional (2D) carbon allotrope with the atoms arranged in a honeycomb lattice. The low-energy electronic excitations in this 2D crystal are described by massless Dirac fermions that have a linear dispersion relation…

We investigate the conductance of normal-conductor/graphene/normal-conductor (NGN) junctions for arbitrary on-site potentials in the normal and graphitic parts of the system. We find that a ballistic NGN junction can display insulating…

Creation of sharp lateral p-n junctions in graphene devices, with transition widths well below the Fermi wavelength of graphene charge carriers, is vital to study and exploit these electronic systems for electron-optical applications. The…

The recent discovery of methods to isolate graphene, a one-atom-thick layer of crystalline carbon, has raised the possibility of a new class of nano-electronics devices based on the extraordinary electrical transport and unusual physical…

The intrinsic values of the carriers mobility and density of the graphene layers inside graphite, the well known structure built on these layers in the Bernal stacking configuration, are not well known mainly because most of the research…

Double-gated graphene devices provide an important platform for understanding electrical and optical properties of graphene. Here we present transport measurements of single layer, bilayer and trilayer graphene devices with suspended top…

We have fabricated and measured ballistic graphene transistors with two oblique gates that can be independently biased. The gate lengths are about 38 nm and are separated by a distance of 30 nm, the tilting angle being of 45o with respect…

We use scanning gate microscopy to map out the trajectories of ballistic carriers in high-mobility graphene encapsulated by hexagonal boron nitride and subject to a weak magnetic field. We employ a magnetic focusing geometry to image…

We have developed a device fabrication process to pattern graphene into nanostructures of arbitrary shape and control their electronic properties using local electrostatic gates. Electronic transport measurements have been used to…

We propose the theory of transport in a gate-tunable graphene p-n junction, in which the gradient of the carrier density is controlled by the gate voltage. Depending on this gradient and on the density of charged impurities, the junction…

We investigate the transport of electrons in disordered and pristine graphene devices. Fano shot noise, a standard metric to assess the mechanism for electronic transport in mesoscopic devices, has been shown to produce almost the same…

Electrostatic gating lies in the heart of modern FET-based integrated circuits. Usually, the gate electrode has to be placed very close to the conduction channel, typically a few nanometers, in order to achieve efficient tunability.…

We report the study of graphene devices in Hall-bar geometry, gated with a polymer electrolyte. High densities of 6 $\times 10^{13}/cm^{2}$ are consistently reached, significantly higher than with conventional back-gating. The mobility…