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Related papers: Transport through graphene double dots

200 papers

We study the thermoelectrical transports for an interacting dot attached to two graphene electrodes. Graphene band structure shows a pseudogap density of states that affects strongly the transport properties. In this work, we focus on the…

Mesoscale and Nanoscale Physics · Physics 2016-01-12 Jose Ramon Isern-Lozano , Ioan Grosu , Rosa Lopez , Jong Soo Lim , Mircea Crisan

We study theoretically a quantum dot in the quantum Hall regime that is strongly coupled to a single lead via a point contact. We find that even when the transmission through the point contact is perfect, important features of the Coulomb…

Condensed Matter · Physics 2009-10-28 Hangmo Yi , C. L. Kane

A quantum dot has been etched in bilayer graphene connected by two small constrictions to the leads. We show that this structure does not behave like a single quantum dot but consists of at least three sites of localized charge in series.…

Mesoscale and Nanoscale Physics · Physics 2014-06-23 Dominik Bischoff , Anastasia Varlet , Pauline Simonet , Thomas Ihn , Klaus Ensslin

A new theoretical method is introduced to study coherent electron transport in an interacting multilevel quantum dot. The method yields the correct behavior both in the limit of weak and strong coupling to the leads, giving a unified…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 A. Levy Yeyati , F. Flores , A. Martin-Rodero

Exchange-coupled singlet-triplet spin qubits in two gate-defined double quantum dots are considered theoretically. Using charge density operators to describe the double-dot orbital states, we calculate the Coulomb couplings between the…

Mesoscale and Nanoscale Physics · Physics 2015-05-28 Guy Ramon

We consider a lateral double-dot system in the Coulomb blockade regime with a single spin-1/2 on each dot, mutually coupled by an anti-ferromagnetic exchange interaction. Each of the two dots is contacted by two leads. We demonstrate that…

Strongly Correlated Electrons · Physics 2007-08-06 V. Koerting , P. Wölfle , J. Paaske

We present electrical transport measurements of a van-der-Waals heterostructure consisting of a graphene nanoribbon separated by a thin boron nitride layer from a micron-sized graphene sheet. The interplay between the two layers is…

Mesoscale and Nanoscale Physics · Physics 2015-05-29 D. Bischoff , M. Eich , A. Varlet , P. Simonet , T. Ihn , K. Ensslin

Coupled quantum dots are potential candidates for qubit systems in quantum computing. We use a non-invasive voltage probe to study the evolution of a coupled dot system from a situation where the dots are coupled to the leads to a situation…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 A. W. Rushforth , C. G. Smith , M. D. Godfrey , H. E. Beere , D. A. Ritchie , M. Pepper

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 present electron transport measurements on lithographically defined and etched graphene nanoconstrictions with different aspect ratios including different lengths (L) and widths (W). A roughly length-independent disorder induced…

Mesoscale and Nanoscale Physics · Physics 2011-04-13 B. Terrés , J. Dauber , C. Volk , S. Trellenkamp , U. Wichmann , C. Stampfer

The differential conductance in a suspended few layered graphene sample is fou nd to exhibit a series of quasi-periodic sharp dips as a function of bias at l ow temperature. We show that they can be understood within a simple model of dyn…

Mesoscale and Nanoscale Physics · Physics 2015-05-13 A. Chepelianskii , P. Delplace , A. Shailos , A. Kasumov , R. Deblock , M. Monteverde , M. Ferrier , S. Guéron , H. Bouchiat

We present finite bias transport measurements on a few-electron quantum dot. In the Coulomb blockade regime, strong signatures of inelastic cotunneling occur which can directly be assigned to excited states observed in the non-blockaded…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 R. Schleser , T. Ihn , E. Ruh , K. Ensslin , M. Tews , D. Pfannkuche , D. C. Driscoll , A. C. Gossard

We study transport through a quantum dot side-coupled to two parallel Luttinger liquid leads in the presence of a Coulombic dot-lead interaction. This geometry enables an exact treatment of the inter-lead Coulomb interactions. We find that…

Mesoscale and Nanoscale Physics · Physics 2015-05-27 Florian Elste , David Reichman , Andrew Millis

We report charge transport measurements in a ring-shaped quadruple quantum dot system, composed of two vertically coupled double quantum dots connected in parallel. The vertical coupling introduces an isospin degree of freedom tied to the…

Mesoscale and Nanoscale Physics · Physics 2025-07-15 Shinichi Amaha , Tsuyoshi Hatano , Takashi Nakajima , Seigo Tarucha

We present transport measurements of a tunable silicon metal-oxide-semiconductor double quantum dot device with lateral geometry. Experimentally extracted gate-to-dot capacitances show that the device is largely symmetric under the gate…

Time-dependent transport through two capacitively coupled quantum dots is studied in the framework of the generalized master equation. The Coulomb interaction is included within the exact diagonalization method. Each dot is connected to two…

Mesoscale and Nanoscale Physics · Physics 2010-05-24 Valeriu Moldoveanu , Andrei Manolescu , Vidar Gudmundsson

The optical response of a heavily doped quantum well, with two occupied subbands, has been investigated as a function of the electronic density. It is shown that the two optically active transitions are mutually coupled by dipole-dipole…

Mesoscale and Nanoscale Physics · Physics 2013-01-25 Aymeric Delteil , Angela Vasanelli , Yanko Todorov , Bruno Paulillo , Giorgio Biasiol , Lucia Sorba , Carlo Sirtori

We study resonant tunneling through quantum-dot systems in the presence of strong Coulomb repulsion and coupling to the metallic leads. Motivated by recent experiments we concentrate on (i) a single dot with two energy levels and (ii) a…

Condensed Matter · Physics 2009-10-28 T. Pohjola , J. König , M. M. Salomaa , J. Schmid , H. Schoeller , Gerd Schön

We calculate theoretically the Coulomb drag resistivity for two graphene monolayers spatially separated by a distance "$d$". We show that the frictional drag induced by inter-layer electron-electron interaction goes asymptotically as…

Mesoscale and Nanoscale Physics · Physics 2012-01-04 E. H. Hwang , S. Das Sarma

Electric transport of double gated bilayer graphene devices is studied as a function of charge density and bandgap. A top gate electrode can be used to control locally the Fermi level to create a pn junction between the double-gated and…

Mesoscale and Nanoscale Physics · Physics 2012-01-06 Hiroki Shioya , Michihisa Yamamoto , Saverio Russo , Monica F. Craciun , Seigo Tarucha