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Related papers: Electronic States of Magnetic Quantum Dots

200 papers

We have investigated the electronic states of planar quantum dots at the ZnO interface containing a few interacting electrons in an externally applied magnetic field. In these systems, the electron-electron interaction effects are expected…

Mesoscale and Nanoscale Physics · Physics 2017-05-24 Tapash Chakraborty , Aram Manaselyan , Manuk Barseghyan

In magnetically-doped quantum dots changing the carrier occupancy, from open to closed shells, leads to qualitatively different forms of carrier-mediated magnetic ordering. While it is common to study such nanoscale magnets within a mean…

Mesoscale and Nanoscale Physics · Physics 2015-10-28 J. M. Pientka , R. Oszwałdowski , A. G. Petukhov , J. E. Han , Igor Žutić

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 discuss a new entangled state that has been observed in the conduction across a quantum dot. At Coulomb blockade, electrons from the contacts correlate strongly to those localized in the dot, due to cotunneling processes. Because of the…

Mesoscale and Nanoscale Physics · Physics 2016-08-31 Domenico Giuliano , Benoit Jouault , Arturo Tagliacozzo

Self-assembled optically active quantum dot molecules (QDMs) allow the creation of protected qubits via singlet-triplet spin states. The qubit energy splitting of these states is defined by the tunnel coupling strength and is, therefore,…

We consider a three-port single-level quantum dot system with one input and two output leads. Instead of considering an empty dot, we study the situations that two input electrons co-tunnel through the quantum dot occupied by one or two dot…

Quantum Physics · Physics 2007-05-23 Chih-Lung Chou

The conductance through a finite quantum dot network is studied as a function of inter-dot coupling. As the coupling is reduced, the system undergoes a transition from the antidot regime to the tight binding limit, where Coulomb resonances…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 August Dorn , Thomas Ihn , Klaus Ensslin , Werner Wegscheider , Max Bichler

We study an influence of a finite magnetic field on a small spin-degenerate quantum dot with even number of electrons, attached to metallic leads. It is shown that, under certain conditions, the low energy physics of the system can be…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 M. Pustilnik , Y. Avishai , K. Kikoin

The properties of a two-dimensional electron are investigated in the presence of a circular step magnetic field profile. Both electrons with parabolic dispersion as well as Dirac electrons with linear dispersion are studied. We found that…

Mesoscale and Nanoscale Physics · Physics 2009-07-22 M. Ramezani Masir , A. Matulis , F. M. Peeters

he multiqubit entangled states are coherently controlled in the quantum spin systems composed of $N+1$ interacting antiferromagnetic molecular rings. The tunable intermolecular couplings arise from the local exchange interactions between…

Quantum Physics · Physics 2009-03-17 Xiang Hao , Tao Pan , Taocheng Zang , Shiqun Zhu

The degree of entanglement of an electron with a hole in a vertically coupled self-assembled dot molecule is shown to be tunable by an external electric field. Using atomistic pseudopotential calculations followed by a configuration…

Materials Science · Physics 2009-11-11 Gabriel Bester , Alex Zunger

The ground states of few electrons confined in two vertically coupled quantum rings in the presence of an external magnetic field are studied systematically within the current spin-density functional theory. Electron-electron interactions…

Mesoscale and Nanoscale Physics · Physics 2009-10-05 L. K. Castelano , G. -Q. Hai , B. Partoens , F. M. Peeters

The zero bias conductance of quantum dots coupled to ferromagnetic leads is investigated. In the strong coupling regime, it is found that the conductance is a non-monotonic function of the angle between the magnetisation directions in the…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 J. Fransson

We study the magnetic orbital response of a system of N interacting electrons confined in a two-dimensional geometry and subjected to a perpendicular magnetic field in the finite temperature Hartree-Fock approximation. The electron-electron…

Mesoscale and Nanoscale Physics · Physics 2009-01-23 L. G. G. V. Dias da Silva , Caio H. Lewenkopf , Nelson Studart

By measuring electron tunneling between a ferromagnet and individual energy levels in an aluminum quantum dot, we show how spin-resolved quantum states can be used as filters to determine spin-dependent tunneling rates. We also observe…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 Mandar M. Deshmukh , D. C. Ralph

The effects of spin-orbit coupling on the two-electron spectra in lateral coupled quantum dots are investigated analytically and numerically. It is demonstrated that in the absence of magnetic field the exchange interaction is practically…

Mesoscale and Nanoscale Physics · Physics 2010-04-12 Fabio Baruffa , Peter Stano , Jaroslav Fabian

We investigate Kondo effect and spin blockade observed on a many-electron quantum dot and study the magnetic field dependence. At lower fields a pronounced Kondo effect is found which is replaced by spin blockade at higher fields. In an…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 D. Kupidura , M. C. Rogge , M. Reinwald , W. Wegscheider , R. J. Haug

We show that spin-orbit coupling in a quantum dot molecule allows for coherent manipulation of two electron spin states using Raman transitions. Such two-electron spin states defined by the singlet and triplet states of two exchange coupled…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Hakan E. Türeci , J. M. Taylor , A. Imamoglu

Incompressible (magic) states of vertically coupled quantum dots submitted to strong magnetic fields such that only the lowest Landau level is relevant are studied within an exact diagonalization calculation for N=3, 5 and 6, electrons. We…

Condensed Matter · Physics 2009-11-07 Nuria Barberan , Joan Soto

We study double quantum dots coupled to a quasistatic cavity mode with high mode-volume compression allowing for strong light-matter coupling. Besides the cavity-mediated interaction, electrons in different double quantum dots interact with…

Mesoscale and Nanoscale Physics · Physics 2024-08-23 Valerii K. Kozin , Dmitry Miserev , Daniel Loss , Jelena Klinovaja