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Related papers: Tunable quantum dots in bilayer graphene

200 papers

Here we report from our theoretical studies that in biased bilayer graphene, one can induce phase transitions from an incompressible fractional quantum Hall state to a compressible state by tuning the bandgap at a given electron density.…

Materials Science · Physics 2010-07-26 Vadim M. Apalkov , Tapash Chakraborty

The electronic states of an electrostatically confined cylindrical graphene quantum dot and the electric transport through this device are studied theoretically within the continuum Dirac-equation approximation and compared with numerical…

Mesoscale and Nanoscale Physics · Physics 2011-08-12 G. Pal , W. Apel , L. Schweitzer

The electronic energy gap and total dipole moment of chemically functionalized hexagonal and triangular graphene quantum dots are investigated by the density functional theory. It has been found that the energy gap can be efficiently tuned…

Mesoscale and Nanoscale Physics · Physics 2018-03-14 Hazem Abdelsalam , Hanan Elhaes , Medhat A. Ibrahim

Twisted van der Waals materials provide a tunable platform for investigating two-dimensional superconductivity and quantum phases. Using spectra-imaging scanning tunneling microscopy, we study the superconducting states in twisted bilayer…

We observe the low-lying excitations of a molecular dimer formed by two electrons in a GaAs semiconductor quantum dot in which the number of confined electrons is tuned by optical illumination. By employing inelastic light scattering we…

Mesoscale and Nanoscale Physics · Physics 2010-06-16 Achintya Singha , Vittorio Pellegrini , Aron Pinczuk , Loren N. Pfeiffer , Ken W. West , Massimo Rontani

Magic angle twisted bilayer graphene has emerged as a powerful platform for studying strongly correlated electron physics, owing to its almost dispersionless low-energy bands and the ability to tune the band filling by electrostatic gating.…

Mesoscale and Nanoscale Physics · Physics 2021-07-21 Nikhil Tilak , Xinyuan Lai , Shuang Wu , Zhenyuan Zhang , Mingyu Xu , Raquel de Almeida Ribeiro , Paul C Canfield , Eva Y. Andrei

The few-layer graphene quantum dot provides a promising platform for quantum computing with both spin and valley degrees of freedom. Gate-defined quantum dots in particular can avoid noise from edge disorders. In connection with the recent…

Mesoscale and Nanoscale Physics · Physics 2017-05-11 Haonan Xiong , Wentao Jiang , Yipu Song , Luming Duan

Graphene and bilayer graphene quantum dots are promising hosts for spin qubits with long coherence times. Although recent technological improvements make it possible to confine single electrons electrostatically in bilayer graphene quantum…

The band modulation of the silicene and graphene quantum dots is investigated by a first-principles method. This study includes the ordinary silicene and graphene quantum dots and the embedded quantum dots in the hydrogenated silicene and…

Mesoscale and Nanoscale Physics · Physics 2018-12-24 Bi-Ru Wu

Graphene quantum dots are considered as promising alternatives to quantum dots in III-V semiconductors, e.g., for the use as spin qubits due to their consistency made of light atoms including spin-free nuclei which both imply relatively…

Mesoscale and Nanoscale Physics · Physics 2016-04-20 Markus Morgenstern , Nils Freitag , Aviral Vaid , Marco Pratzer , Marcus Liebmann

We propose a new method to use gapped graphene as barrier to confine electrons in gapless graphene and form a good quantum dot, which can be realized on an oxygen-terminated $SiO_{2}$ substrate partly H-passivated. In particular, we use…

Mesoscale and Nanoscale Physics · Physics 2009-10-27 Qiong Ma , Zhi-Rong Lin , Tao Tu , Guang-Can Guo , Guo-Ping Guo

The rich phase diagram of quantum spin-ladder systems has attracted much attention in the theoretical literature. The progress in experimental realisations of this fascinating physics however has been much slower. While materials with a…

Mesoscale and Nanoscale Physics · Physics 2015-11-05 Victoria Mazo , Chia-Wei Huang , Efrat Shimshoni , Sam T. Carr , H. A. Fertig

We investigate from first principles the electronic and optical properties of edge-modulated armchair graphene nanoribbons, including both quasi-particle corrections and excitonic effects. Exploiting the oscillating behavior of the ribbon…

Materials Science · Physics 2011-04-19 Deborah Prezzi , Daniele Varsano , Alice Ruini , Elisa Molinari

We derive a material-realistic real-space many-body Hamiltonian for twisted bilayer graphene from first principles, including both single-particle hopping terms for $p_z$ electrons and long-range Coulomb interactions. By disentangling low-…

Mesoscale and Nanoscale Physics · Physics 2022-01-24 Tom Westerhout , Mikhail I. Katsnelson , Malte Rösner

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

The non-interacting energy spectrum of graphene and its bilayer counterpart consists of multiple degeneracies owing to the inherent spin, valley and layer symmetries. Interactions among charge carriers are expected to spontaneously break…

Mesoscale and Nanoscale Physics · Physics 2015-05-20 R. Thomas Weitz , Monica T. Allen , Benjamin E. Feldman , Jens Martin , Amir Yacoby

We study analytically and numerically electronic properties of a circular quantum dot made from AA bilayer graphene. We observe a discrete set of dot radii for which the low-energy electron states are degenerate with respect to the layer…

Mesoscale and Nanoscale Physics · Physics 2023-04-24 A. L. Rakhmanov , A. V. Rozhkov , A. O. Sboychakov

We present transport measurements through an electrostatically defined bilayer graphene double quantum dot in the single electron regime. With the help of a back gate, two split gates and two finger gates we are able to control the number…

Mesoscale and Nanoscale Physics · Physics 2020-04-22 Luca Banszerus , Samuel Möller , Eike Icking , Kenji Watanabe , Takashi Taniguchi , Christian Volk , Christoph Stampfer

The unique property of bilayer graphene to show a band gap tunable by external electrical fields enables a variety of different device concepts with novel functionalities for electronic, optoelectronic and sensor applications. So far the…

Materials Science · Physics 2016-09-21 Bartholomaeus N. Szafranek , Daniel Schall , Martin Otto , Daniel Neumaier , Heinrich Kurz

Unlike single layer graphene, in the case of $AB$-stacked bilayer graphene (BLG) one can induce a non-zero energy gap by breaking the inversion symmetry between the two layers using a perpendicular electric field. This is an essential…

Mesoscale and Nanoscale Physics · Physics 2018-09-05 G. A. Nemnes , T. L. Mitran , A. Manolescu , Daniela Dragoman