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Related papers: Electron-Hole Crossover in Graphene Quantum Dots

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Probing techniques with spatial resolution have the potential to lead to a better understanding of the microscopic physical processes and to novel routes for manipulating nanostructures. We present scanning-gate images of a graphene quantum…

Mesoscale and Nanoscale Physics · Physics 2012-06-13 S. Schnez , J. Güttinger , M. Huefner , C. Stampfer , K. Ensslin , T. Ihn

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…

Mesoscale and Nanoscale Physics · Physics 2016-06-01 K. V. Germash , D. V. Fil

The recent Quantum Hall experiments in graphene have confirmed the theoretically well-understood picture of the quantum Hall (QH) conductance in fermion systems with continuum Dirac spectrum. In this paper we take into account the lattice,…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 B. Andrei Bernevig , Taylor L. Hughes , Han-Dong Chen , Congjun Wu , Shou-Cheng Zhang

We investigate single-electron transport through quantum dots with negative charging energy induced by a polaronic energy shift. For weak dot-lead tunnel couplings, we demonstrate a bipolaronic blockade effect at low biases which suppresses…

Mesoscale and Nanoscale Physics · Physics 2015-06-16 Tie-Feng Fang , Shu-Feng Zhang , Chun-Jiang Niu , Qing-feng Sun

We show that the plasmon spectrum of an ordinary two-dimensional electron gas (2DEG) hosted in a GaAs heterostructure is significantly modified when a graphene sheet is placed on the surface of the semiconductor in close proximity to the…

Mesoscale and Nanoscale Physics · Physics 2012-08-21 Alessandro Principi , Matteo Carrega , Reza Asgari , Vittorio Pellegrini , Marco Polini

We report the observation of Coulomb blockade in a quantum dot contacted by two quantum point contacts each with a single fully-transmitting mode, a system previously thought to be well described without invoking Coulomb interactions. At…

Mesoscale and Nanoscale Physics · Physics 2012-04-06 S. Amasha , I. G. Rau , M. Grobis , R. M. Potok , H. Shtrikman , D. Goldhaber-Gordon

We study resonant tunneling through a single-level quantum dot in the presence of strong Coulomb repulsion beyond the perturbative regime. The level is either spin-degenerate or can be split by a magnetic field. We, furthermore, discuss the…

Condensed Matter · Physics 2009-10-28 Jürgen König , Jörg Schmid , Herbert Schoeller , Gerd Schön

Electron transport through parallel double quantum dot system with interdot tunneling and strong on-site Coulomb interaction is studied in the Kondo regime by using the finite-$U$ slave boson technique. For a system of quantum dots with…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 Guo-Hui Ding , C. K. Kim , K. Nahm

We present a device architecture of hybrid-edge and dual-gated quantum point contact. We demonstrate improved electrostatic control over the separation, position, and coupling of each broken-symmetry compressible strip in graphene. Via…

Mesoscale and Nanoscale Physics · Physics 2023-11-27 Wei Ren , Xi Zhang , Jaden Ma , Xihe Han , Kenji Watanabe , Takashi Taniguchi , Ke Wang

Due to Klein tunneling in graphene only quasi-bound states are realized in graphene quantum dots by electrostatic gating. Particles in the quasi-bound states are trapped inside the dot for a finite time and they keep bouncing back and forth…

Mesoscale and Nanoscale Physics · Physics 2018-08-29 Abdelhadi Belouad , Youness Zahidi , Ahmed Jellal , Hocine Bahlouli

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

The temperature dependence of Coulomb blockade peak height correlation is used to investigate how adding electrons to a quantum dot alters or "scrambles" its electronic spectrum. Deviations from finite-temperature random matrix theory with…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 S. R. Patel , D. R. Stewart , C. M. Marcus , M. Gokcedag , Y. Alhassid , A. D. Stone , C. I. Duruoz , J. S. Harris

An electrostatic quantum dot cannot be formed in monolayer graphene, because of the Klein tunnelling. However, a dot can be formed with the help of a uniform magnetic field. As shown here, a spatial modulation of the Dirac gap leads to…

Mesoscale and Nanoscale Physics · Physics 2015-05-27 G. Giavaras , Franco Nori

We obtain the solution of the Dirac equation in (2+1) dimensions in the presence of a constant magnetic field normal to the plane together with a two-dimensional Dirac-oscillator potential coupling. We study the energy spectrum of graphene…

Mesoscale and Nanoscale Physics · Physics 2016-02-17 Abdelhadi Belouad , Ahmed Jellal , Youness Zahidi

We investigate cross-correlations in the tunneling currents through two parallel quantum dots coupled to independent electrodes and gates and interacting via an inter-dot Coulomb interaction. The correlations reveal additional information,…

Mesoscale and Nanoscale Physics · Physics 2008-02-26 Sebastian Haupt , Jasmin Aghassi , Matthias H. Hettler , Gerd Sch"on

In this article we investigate the excitations in a single graphene layer and in a single-walled carbon nanotube, i.e. the spectrum of magnetic excitations is calculated. In the absence of interactions in these systems there is a unique gap…

Strongly Correlated Electrons · Physics 2015-06-19 Vladimir Posvyanskiy , Logi Arnarson , Per Hedegård

We report distinctive magnetotransport properties of a graphene p-n-p junction prepared by controlled diffusion of metallic contacts. In most cases, materials deposited on a graphene surface introduce substantial carrier scattering, which…

Mesoscale and Nanoscale Physics · Physics 2016-02-17 Cheng-Hua Liu , Po-Hsiang Wang , Tak-Pong Woo , Fu-Yu Shih , Shih-Ching Liou , Po-Hsun Ho , Chun-Wei Chen , Chi-Te Liang , Wei-Hua Wang

Electronic structure of graphene monolayer-bilayer junction in a magnetic field is studied within an effective-mass approximation. The energy spectrum is characterized by interface Landau levels, i.e., the locally flat bands appearing near…

Mesoscale and Nanoscale Physics · Physics 2015-05-19 Mikito Koshino , Takeshi Nakanishi , Tsuneya Ando

The Coulomb gap observed in tunneling between parallel two-dimensional electron systems, each at half filling of the lowest Landau level, is found to depend sensitively on the presence of an in-plane magnetic field. Especially at low…

Mesoscale and Nanoscale Physics · Physics 2016-09-14 J. P. Eisenstein , T. Khaire , D. Nandi , A. D. K. Finck , L. N. Pfeiffer , K. W. West

We propose a transport blockade mechanism in quantum dot arrays and conducting molecules based on an interplay of Coulomb repulsion and the formation of edge states. As a model we employ a dimer chain that exhibits a topological phase…

Mesoscale and Nanoscale Physics · Physics 2016-03-30 Mónica Benito , Michael Niklas , Gloria Platero , Sigmund Kohler