相关论文: Contacts and upstream modes explain the electron-h…
Graphitic nitrogen-doped graphene is an excellent platform to study scattering processes of massless Dirac fermions by charged impurities, in which high mobility can be preserved due to the absence of lattice defects through direct…
Low-energy transport measurements in Quantum Hall systems have been argued to be governed by emergent modular symmetries whose predictions are robust against many of the detailed microscopic dynamics. We propose the recently-observed…
Quantum Hall effect (QHE), the ground to construct modern conceptual electronic systems with emerging physics, is often much influenced by the interplay between the host two-dimensional electron gases and the substrate, sometimes predicted…
The formation of quantum Hall channels inside the bulk of graphene is studied using various contact and gate geometries. p-n junctions are created along the longitudinal direction of samples, and enhanced conductance is observed in the case…
We review the basic aspects of electrons in graphene (two-dimensional graphite) exposed to a strong perpendicular magnetic field. One of its most salient features is the relativistic quantum Hall effect the observation of which has been 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…
The influence of magnetic impurities on the transport properties of graphene is investigated in the regime of strong applied electric fields. As a result of electron-hole pair creation, the response becomes nonlinear and dependent on the…
Metal contacts have been identified to be a key technological bottleneck for the realization of viable graphene electronics. Recently, it was observed that for structures that possess both a top and a bottom gate, the electron-hole…
In the recent years many researches were performed about graphene. Graphene is always considered a half metal or a zero gap semiconductor. In the last year new experiments were done about graphene on boron nitride and they obtained an…
We theoretically investigate the effects of long-range disorder and electron-electron interactions on the optical properties of hexagonal armchair graphene quantum dots consisting of up to 10806 atoms. The numerical calculations are…
The superconducting pairing of electrons in doped graphene due to in-plane and out-of-plane phonons is considered. It is shown that the structure of the order parameter in the valley space substantially affects conditions of the pairing.…
The effect of an inhomogeneous magnetic field which varies inversely as distance on the ground state energy level of graphene is studied. In this work, we analytically show that graphene under the influence of a magnetic field arising from…
We study the effect of local modulation of charge density and carrier type in graphene field effect transistors using a double top gate geometry. The two top gates lead to the formation of multiple \emph{p-n} junctions. Electron transport…
We model the quantum Hall effect in heterostructures made of two gapped graphene stripes with different gaps, $\Delta_1$ and $\Delta_2$. We consider two main situations, $\Delta_1=0,\Delta_2\neq0$ and $\Delta_1=-\Delta_2$. They are…
We report on a first-principles study of the conductance through graphene suspended between Al contacts as a function of junction length, width, and orientation. The charge transfer at the leads and into the freestanding section gives rise…
We present an approach to the fractional quantum Hall effect observed in grapheme (GFQHE), basing us on the model developed previously for the fractional quantum Hall effect in a two-dimensional electron system embedded in a quantum well…
Manipulating electron quantum 1D channels is an important element in the field of quantum information due to their ballistic and phase coherence properties. In GaAs and graphene based two dimensional gas systems, these edge channels have…
We study electromagnetic properties of a double layer graphene system in which electrons from one layer are coupled with holes from the other layer. The gauge invariant linear response functions are obtained. The frequency dependences of…
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…
Using in-situ Raman scattering from phosphorene channel in an electrochemically top-gated field effect transistor, we show that its phonons with A$_g$ symmetry depend much more strongly on concentration of electrons than that of holes,…