English
Related papers

Related papers: Graphene quantum dots: Beyond a Dirac billiard

200 papers

We study the quantization of Dirac fermions in lithographically defined graphene nanoconstrictions. We observe quantized conductance in single nanoconstrictions fabricated on top of a thin hexamethyldisilazane layer over a Si/SiO_2 wafer.…

Using low-temperature scanning tunneling spectroscopy, we map the local density of states (LDOS) of graphene quantum dots supported on Ir(111). Due to a band gap in the projected Ir band structure around the graphene K point, the electronic…

Graphene quantum dots are attractive candidates for solid-state quantum bits. In fact, the predicted weak spin-orbit and hyperfine interaction promise spin qubits with long coherence times. Graphene quantum dot devices have been extensively…

Quantum confinement of graphene Dirac-like electrons in artificially crafted nanometer structures is a long sought goal that would provide a strategy to selectively tune the electronic properties of graphene, including bandgap opening or…

In this chapter, semi-analytical models for the calculation of the quantum capacitance of both monolayer and bilayer graphene and its nanoribbons, are presented. Since electron-hole puddles are experimental facts in all graphene samples,…

Mesoscale and Nanoscale Physics · Physics 2016-09-07 George S. Kliros

We theoretically analyse the possibility to electrostatically confine electrons in circular quantum dot arrays, impressed on contacted graphene nanoribbons by top gates. Utilising exact numerical techniques, we compute the scattering…

Mesoscale and Nanoscale Physics · Physics 2016-04-21 Holger Fehske , Georg Hager , Andreas Pieper

The edges of graphene and graphene like systems can host localized states with evanescent wave function with properties radically different from those of the Dirac electrons in bulk. This happens in a variety of situations, that are…

Mesoscale and Nanoscale Physics · Physics 2016-09-20 J. L. Lado , N. Garcia-Martinez , J. Fernandez-Rossier

We report an approach to confine the carriers in single-layer graphene, which leads to quantum devices with field-induced quantum confinement. We demonstrated that the Coulomb-blockade effect evolves under a uniform magnetic field…

Mesoscale and Nanoscale Physics · Physics 2017-09-21 S. Moriyama , Y. Morita , E. Watanabe , D. Tsuya

Confinement of electrons in graphene to make devices has proven to be a challenging task. Electrostatic methods fail because of Klein tunneling, while etching into nanoribbons requires extreme control of edge terminations, and bottom-up…

Mesoscale and Nanoscale Physics · Physics 2018-04-03 Y. Wu , D. Zhai , C. Pan , B. Cheng , T. Taniguchi , K. Watanabe , N. Sandler , M. Bockrath

In the presence of axial magnetic fields that can be realized in deliberately buckled monolayer graphene, quasi-relativistic Dirac fermions may find themselves in a variety of broken symmetry phases even for weak interactions. Through a…

Mesoscale and Nanoscale Physics · Physics 2014-09-03 Bitan Roy , Jay D. Sau

Graphene has been proposed as a promising material for future nanoelectronics because of its unique electronic properties. Understanding the scaling behavior of this new nanomaterial under common experimental conditions is of critical…

Mesoscale and Nanoscale Physics · Physics 2015-05-27 Yang Sui , Tony Low , Mark Lundstrom , Joerg Appenzeller

Considerable efforts have been made to trap massless Dirac fermions in graphene monolayer, but only quasi-bound states are realized in continuous graphene sheets up to now. Here, we demonstrate the realization of bound states in nanoscale…

Mesoscale and Nanoscale Physics · Physics 2017-04-05 Jia-Bin Qiao , Hua Jiang , Haiwen Liu , Hong Yang , Ning Yang , Kai-Yao Qiao , Lin He

Two-dimensional carbon, or graphene, is a semi-metal that presents unusual low-energy electronic excitations described in terms of Dirac fermions. We analyze in a self-consistent way the effects of localized (impurities or vacancies) and…

Strongly Correlated Electrons · Physics 2009-11-11 N. M. R. Peres , F. Guinea , A. H. Castro Neto

We present extensive numerical results for the thermodynamic density of states (i.e. quantum capacitance) of a two-dimensional massless Dirac fermion fluid in a doped graphene sheet. In particular, by employing the random phase…

Mesoscale and Nanoscale Physics · Physics 2014-10-23 Reza Asgari , Mikhail I. Katsnelson , Marco Polini

We develop a theory for the compressibility and quantum capacitance of disordered monolayer and bilayer graphene including the full hyperbolic band structure and band gap in the latter case. We include the effects of disorder in our theory,…

Mesoscale and Nanoscale Physics · Physics 2011-03-09 D. S. L. Abergel , E. H. Hwang , S. Das Sarma

We report on numerical study of the Dirac fermions in partially filled N=3 Landau level (LL) in graphene. At half-filling, the equal-time density-density correlation function displays sharp peaks at nonzero wavevectors $\pm {\bf q^{*}}$.…

Strongly Correlated Electrons · Physics 2008-03-31 Hao Wang , D. N. Sheng , L. Sheng , F. D. M. Haldane

We study the electronic and magnetic properties of multilayer quantum dots (MQDs) of graphite in the nearest-neighbor approximation of tight-binding model. We calculate the electronic density of states and orbital susceptibility of the…

Mesoscale and Nanoscale Physics · Physics 2015-01-19 Hazem Abdelsalam , Tania Espinosa-Ortega , Igor Lukyanchuk

We present electronic transport measurements through short and narrow (30x30 nm) single layer graphene constrictions on a hexagonal boron nitride substrate. While the general observation of Coulomb-blockade is compatible with earlier work,…

Mesoscale and Nanoscale Physics · Physics 2015-01-30 Dominik Bischoff , Florian Libisch , Joachim Burgdörfer , Thomas Ihn , Klaus Ensslin

By applying the infinite-mass boundary condition, we analytically calculate the confined states and the corresponding wave functions of AA-stacked bilayer graphene quantum {dots} in the presence of an uniform magnetic field $B$. It is found…

Mesoscale and Nanoscale Physics · Physics 2016-02-29 Abdelhadi Belouad , Youness Zahidi , Ahmed Jellal

We study matrix element fluctuations of the two-body screened Coulomb interaction and of the one-body surface charge potential in ballistic quantum dots, comparing behavior in actual chaotic billiards with analytic results previously…

Mesoscale and Nanoscale Physics · Physics 2011-06-29 L. Kaplan , Y. Alhassid