English
Related papers

Related papers: Spin States in Graphene Quantum Dots

200 papers

We have carried out first-principles calculations on electronic properties of graphene quantum dots embedded in hexagonal boron nitride monolayer sheets. The calculations with density functional theory show that the band gaps of quantum…

Mesoscale and Nanoscale Physics · Physics 2015-05-20 Junwen Li , Vivek B. Shenoy

We calculate that the electron states of strained self-assembled Ge/Si quantum dots provide a convenient two-state system for electrical control. An electronic state localized at the apex of the quantum dot is nearly degenerate with a state…

Mesoscale and Nanoscale Physics · Physics 2015-05-14 C. E. Pryor , M. E. Flatté , J. Levy

We study graphene which has both spin-orbit coupling (SOC), taken to be of the Kane-Mele form, and a Zeeman field induced due to proximity to a ferromagnetic material. We show that a zigzag interface of graphene having SOC with its pristine…

Mesoscale and Nanoscale Physics · Physics 2016-02-17 Ranjani Seshadri , K. Sengupta , Diptiman Sen

The discovery of alternating superconducting and insulating ground-states in magic angle graphene has suggested an intriguing analogy with cuprate high-$T_c$ materials. Here we argue that the network states of small angle twisted bilayer…

Strongly Correlated Electrons · Physics 2020-10-02 E. J. König , Piers Coleman , A. M. Tsvelik

The spin of an electron in a self-assembled InAs/GaAs quantum dot molecule is optically prepared and measured through the trion triplet states. A longitudinal magnetic field is used to tune two of the trion states into resonance, forming a…

An exhaustive ground-state analysis of extended two-dimensional (2D) correlated spin-electron model consisting of the Ising spins localized on nodal lattice sites and mobile electrons delocalized over pairs of decorating sites is performed…

Strongly Correlated Electrons · Physics 2018-05-23 Hana Čenčariková , Jozef Strečka , Andrej Gendiar , Natália Tomašovičová

We consider a class of ground states for quantum spin chains on an integer lattice. First we show that presence of the spectral gap between the ground state energy and the rest of spectrum implies the split property of certain subsystems.As…

Mathematical Physics · Physics 2008-08-12 Taku Matsui

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

We report on measurements of the quantum capacitance in graphene as a function of charge carrier density. A resonant LC-circuit giving high sensitivity to small capacitance changes is employed. The density of states, which is directly…

Mesoscale and Nanoscale Physics · Physics 2010-07-28 S. Dröscher , P. Roulleau , F. Molitor , P. Studerus , C. Stampfer , T. Ihn , K. Ensslin

We study the effects of thickness on the ground states of two-dimensional quantum dots in high magnetic fields. To be specific, we assume the thickness to be small so that only the lowest state in the corresponding direction is occupied,…

Mesoscale and Nanoscale Physics · Physics 2009-02-03 E. Tölö , A. Harju

We present detailed spectral calculations for small Lieb lattices having up to $N=4$ number of cells, in the regime of half-filling, an instance of particular relevance for the nano-magnetism of discrete systems such as quantum dot arrays,…

Mesoscale and Nanoscale Physics · Physics 2016-10-12 M. Tolea , M. Nita

Energy spectroscopy of strongly interacting phases requires probes which minimize screening while retaining spectral resolution and local sensitivity. Here we demonstrate that such probes can be realized using atomic sized quantum dots…

Mesoscale and Nanoscale Physics · Physics 2020-08-26 Itai Keren , Tom Dvir , Ayelet Zalic , Amir Iluz , David LeBoeuf , Kenji Watanabe , Takashi Taniguchi , Hadar Steinberg

In 2005 Kane & Mele[C. L. Kane and E. J. Mele, Phys. Rev. Lett. 95, 226801 (2005)], predicted that at sufficiently low energy, graphene exhibits a topological state of matter with an energy gap generated by the atomic spin-orbit…

Mesoscale and Nanoscale Physics · Physics 2019-02-06 Jonas Sichau , Marta Prada , Timothy J. Lyon , Bojan Bosnjak , Tim Anlauf , Lars Tiemann , Robert H. Blick

Owing to the spin, valley, and orbital symmetries, the lowest Landau level (LL) in bilayer graphene exhibits multicomponent quantum Hall ferromagnetism. Using transport spectroscopy, we investigate the energy gaps of integer and fractional…

Mesoscale and Nanoscale Physics · Physics 2016-03-23 Yanmeng Shi , Yongjin Lee , Shi Che , Ziqi Pi , Timothy Espiritu , Petr Stepanov , Dmitry Smirnov , Chun Ning Lau , Fan Zhang

We present measurements on spin blockade in a laterally integrated quantum dot. The dot is tuned into the regime of strong Coulomb blockade, confining ~ 50 electrons. At certain electronic states we find an additional mechanism suppressing…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 A. K. Huettel , H. Qin , A. W. Holleitner , R. H. Blick , K. Neumaier , D. Weinmann , K. Eberl , J. P. Kotthaus

The ground-state electron density of a one-dimensional spin-orbit coupled quantum dot with a Zeeman term and strong electron interaction is studied at the fractional helical liquid points. We show that at fractional filling factors…

Mesoscale and Nanoscale Physics · Physics 2015-12-23 F. Cavaliere , F. M. Gambetta , S. Barbarino , M. Sassetti

We theoretically investigate the spectrum of a single electron double quantum dot, defined by top gates in a graphene with a substrate induced gap. We examine the effects of electric and magnetic fields on the spectrum of localized states,…

Mesoscale and Nanoscale Physics · Physics 2014-02-20 Martin Raith , Christian Ertler , Peter Stano , Michael Wimmer , Jaroslav Fabian

We propose a generalized Dirac fermion description for the electronic state of graphene terminated by a zigzag edge. This description admits a spin-orbit coupling needed to preserve time-reversal invariance of the zigzag confinement,…

Mesoscale and Nanoscale Physics · Physics 2011-07-20 Grigory Tkachov , Martina Hentschel

In this article, we consider fixed spin 1/2 particles interacting through the quantized electromagnetic field in a constant magnetic field. We give some asymptotic expansions for the ground state and the ground state energy of the…

Mathematical Physics · Physics 2016-03-29 Laurent Amour , Jean Nourrigat

We study the magnetic properties of nanometer-sized graphene structures with triangular and hexagonal shapes terminated by zig-zag edges. We discuss how the shape of the island, the imbalance in the number of atoms belonging to the two…

Mesoscale and Nanoscale Physics · Physics 2007-10-30 J. Fernandez-Rossier , J. J. Palacios