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Related papers: Mass-profile quantum dots in graphene

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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 and its multilayers have attracted considerable interest owing to the fourfold spin and valley degeneracy of their charge carriers, which enables the formation of a rich variety of broken-symmetry states and raises the prospect of…

Mesoscale and Nanoscale Physics · Physics 2013-09-10 Benjamin E. Feldman , Andrei J. Levin , Benjamin Krauss , Dmitry Abanin , Bertrand. I. Halperin , Jurgen H. Smet , Amir Yacoby

We investigate the way that the degenerate manifold of midgap edge states in quasicircular graphene quantum dots with zig-zag boundaries supports, under free-magnetic-field conditions, strongly correlated many-body behavior analogous to the…

Mesoscale and Nanoscale Physics · Physics 2016-09-08 Igor Romanovsky , Constantine Yannouleas , Uzi Landman

Quantum dots are fabricated in a Ga[Al]As-heterostructure by local oxidation with an atomic force microscope. This technique, in combination with top gate voltages, allows us to generate steep walls at the confining edges and small lateral…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 A. Fuhrer , S. Luescher , T. Heinzel , K. Ensslin , W. Wegscheider , M. Bichler

Quantum dots induced by a strong magnetic field applied to a single layer of graphene in the perpendicular direction are investigated. The dot is defined by a model potential which consists of a well of depth $\Delta V$ relative to a flat…

Mesoscale and Nanoscale Physics · Physics 2015-05-19 P. A. Maksym , M. Roy , M. F. Craciun , M. Yamamoto , S. Tarucha , H. Aoki

We investigate the electronic eigenstates of graphene quantum dots of realistic size (i.e., up to 80 nm diameter) in the presence of a perpendicular magnetic field B. Numerical tight-binding calculations and Coulomb-blockade measurements…

Mesoscale and Nanoscale Physics · Physics 2010-06-09 F. Libisch , S. Rotter , J. Güttinger , C. Stampfer , J. Burgdörfer

We combine electrostatic and magnetic confinement to define a quantum dot in bilayer graphene. The employed geometry couples $n$-doped reservoirs to a $p$-doped dot. At magnetic field values around $B = 2~$T, Coulomb blockade is observed.…

Mesoscale and Nanoscale Physics · Physics 2018-03-19 Hiske Overweg , Peter Rickhaus , Marius Eich , Yongjin Lee , Riccardo Pisoni , Kenji Watanabe , Takashi Taniguchi , Thomas Ihn , Klaus Ensslin

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…

Mesoscale and Nanoscale Physics · Physics 2017-02-08 A. Altıntaş , K. E. Çakmak , A. D. Güçlü

When electrons populate a flat band their kinetic energy becomes negligible, forcing them to organize in exotic many-body states to minimize their Coulomb energy. The zeroth Landau level of graphene under magnetic field is a particularly…

We analyze the single particle states at the edges of disordered graphene quantum dots. We show that generic graphene quantum dots support a number of edge states proportional to circumference of the dot over the lattice constant. Our…

Mesoscale and Nanoscale Physics · Physics 2010-07-13 M. Wimmer , A. R. Akhmerov , F. Guinea

Topologically protected chiral states at a mass-inverted quantum dot in graphene are studied by analyzing both tight-binding and kernal polynomial method calculations. The mass-inverted quantum dot is introduced by considering a…

Mesoscale and Nanoscale Physics · Physics 2021-02-24 Nojoon Myoung

We study a quasi-one-dimensional attractive Bose gas confined in an optical lattice with a superimposed harmonic potential by analyzing the effective one-dimensional Bose-Hubbard Hamiltonian of the system. In order to have a reliable…

Quantum Gases · Physics 2014-10-01 Luca Barbiero , Luca Salasnich

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

Due to the advantage of tunability via size, shape, doping and relatively low level of loss and high extent of spatial confinement, graphene quantum dots (GQDs) are emerging as an effective way to control light by molecular engineering. The…

Materials Science · Physics 2015-02-13 Sharma S. R. K. C Yamijala , Madhuri Mukhopadhyay , Swapan K. Pati

Flat band moir\'e graphene systems have emerged as a quintessential platform to investigate correlated phases of matter. A plethora of interaction-driven ground states have been proposed, and yet despite extensive experimental effort, there…

This work investigates the electronic properties of the energy spectrum of a hybrid system composed of (i) a circular quantum dot of monolayer graphene surrounded by an infinite sheet of AA-stacked bilayer graphene and (ii) a circular…

Mesoscale and Nanoscale Physics · Physics 2021-08-02 Abdelhadi Belouad , Abdellatif Kamal , El Bouâzzaoui Choubabi , Rachid Houça , Mohammed El Bouziani

We use numerical simulations to predict peculiar magnetotransport fingerprints in polycrystalline graphene, driven by the presence of grain boundaries of varying size and orientation. The formation of Landau levels is shown to be restricted…

Mesoscale and Nanoscale Physics · Physics 2014-10-06 Aron W. Cummings , Alessandro Cresti , Stephan Roche

We study the effects of a magnetic flux and an inhomogeneous gap on the energy spectrum of graphene magnetic quantum dots (GMQDs). By considering the Dirac equation in the infinite mass framework, we can analytically obtain eigenspinor…

Mesoscale and Nanoscale Physics · Physics 2024-05-28 Mohammed El Azar , Ahmed Bouhlal , Ahmed Jellal

Massless Dirac particles cannot be confined by an electrostatic potential. This is a problem for making graphene quantum dots but confinement can be achieved with a magnetic field and here, general conditions for confined and deconfined…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 G. Giavaras , P. A. Maksym , M. Roy

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