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Related papers: Effect of disorder on a graphene p-n junction

200 papers

We study the transport of charge carriers through finite graphene structures. The use of numerical exact kernel polynomial and Green function techniques allows us to treat actual sized samples beyond the Dirac-cone approximation.…

Mesoscale and Nanoscale Physics · Physics 2013-11-13 A. Pieper , G. Schubert , G. Wellein , H. Fehske

Carrier transport in gated 2D graphene monolayers is theoretically considered in the presence of scattering by random charged impurity centers with density $n_i$. Excellent quantitative agreement is obtained (for carrier density $n >…

Mesoscale and Nanoscale Physics · Physics 2007-10-09 E. H. Hwang , S. Adam , S. Das Sarma

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…

Mesoscale and Nanoscale Physics · Physics 2011-08-12 Jairo Velasco , Gang Liu , Wenzhong Bao , Chun Ning Lau

We develop a theory for density, disorder, and temperature dependent electrical conductivity of bilayer graphene in the presence of long-range charged impurity scattering as well as an additional short-range disorder of independent origin,…

Mesoscale and Nanoscale Physics · Physics 2010-04-21 S. Das Sarma , E. H. Hwang , E. Rossi

We study a suspended graphene sheet subject to the electric field of a gate underneath. We compute the elastic deformation of the sheet and the corresponding effective gauge field, which modifies the electronic transport. In a clean system…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 M. M. Fogler , F. Guinea , M. I. Katsnelson

We study the the transport properties of multiterminal ballistic graphene samples, concentrating on the conductance matrix, fluctuations and cross-correlations. Far away from Dirac point, the current is carried mostly by propagating modes…

Mesoscale and Nanoscale Physics · Physics 2010-09-03 M. A. Laakso , T. T. Heikkilä

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…

Mesoscale and Nanoscale Physics · Physics 2012-03-09 Ajay K. Bhat , Vibhor Singh , Sunil Patil , Mandar M. Deshmukh

The quantum Hall effect in graphene p-n junctions is studied numerically with emphasis on the effect of disorder at the interface of two adjacent regions. Conductance plateaus are found to be attached to the intensity of the disorder, and…

Mesoscale and Nanoscale Physics · Physics 2009-04-06 Jian Li , Shun-Qing Shen

One of the unique features of graphene is that the Fermi wavelength of its charge carriers can be tuned electrostatically over a wide range. This allows in principle to tune the transparency of a pn-junction electrostatically, as this…

Graphene's linear dispersion relation and the attendant implications for bipolar electronics applications have motivated a range of experimental efforts aimed at producing p-n junctions in graphene. Here we report electrical transport…

We calculate the carrier density dependent ground state properties of graphene in the presence of random charged impurities in the substrate taking into account disorder and interaction effects non-perturbatively on an equal footing in a…

Mesoscale and Nanoscale Physics · Physics 2008-10-17 Enrico Rossi , S. Das Sarma

Recent experimental work on locally gated graphene layers resulting in p-n junctions have revealed quantum Hall effect in their transport behavior. We explain the observed conductance quantization which is fractional in the bipolar regime…

Mesoscale and Nanoscale Physics · Physics 2007-08-07 D. A. Abanin , L. S. Levitov

In Dirac materials, the low energy excitations behave like ultra-relativistic massless particles with linear energy dispersion. A particularly intriguing phenomenon arises with the intrinsic charge transport behavior at the Dirac point…

Mesoscale and Nanoscale Physics · Physics 2016-07-12 Piranavan Kumaravadivel , Xu Du

The feasibility of Veselago lensing in graphene with a p-n junction is investigated numerically for realistic injection leads. Two different set-ups with two narrow leads are considered with absorbing or reflecting side edges. This allows…

Mesoscale and Nanoscale Physics · Physics 2015-09-09 S. P. Milovanovic , D. Moldovan , F. M. Peeters

We analyze the effect of screening provided by the additional graphene layer in double layer graphene heterostructures (DLGs) on transport characteristics of DLG devices in the metallic regime. The effect of gate-tunable charge density in…

Mesoscale and Nanoscale Physics · Physics 2012-11-16 K. Kechedzhi , E. H. Hwang , S. Das Sarma

The coherent charge transport through an illuminated graphene ribbon is studied as function of electronic doping, frequency and strength of the electromagnetic driving, for monochromatic circularly polarized light. We focus on the DC…

Mesoscale and Nanoscale Physics · Physics 2017-12-13 Jonathan Atteia , Jens. H. Bardarson , Jérome Cayssol

We derive the local density of states from itinerant and boundary states around transport barriers and edges in graphene and show that the itinerant states lead to mesoscale undulations that could be used to probe their scattering…

Mesoscale and Nanoscale Physics · Physics 2015-04-17 Daniel Gunlycke , Carter T. White

We use the non-equilibrium Green function (NEGF) method in the ballistic limit to provide a quantitative description of the conductance of graphene pn junctions - an important building block for graphene electronics devices. In this paper,…

Mesoscale and Nanoscale Physics · Physics 2009-06-06 Tony Low , Seokmin Hong , Joerg Appenzeller , Supriyo Datta , Mark Lundstrom

We present a method for obtaining quantum transport properties in graphene that uniquely combines three crucial features: microscopic treatment of charge disorder, fully quantum mechanical analysis of transport, and the ability to model…

Mesoscale and Nanoscale Physics · Physics 2010-03-12 E. Rossi , J. H. Bardarson , P. W. Brouwer , S. Das Sarma

Graphene charge carriers behave as relativistic massless fermions, thereby exhibiting a variety of counter-intuitive behaviors. In particular, at p-n junctions, they behave as photons encountering a negative index media, therefore…