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We discuss an exactly solvable model Hamiltonian for describing the interacting electron gas in a quantum dot. Results for a spherical square well confining potential are presented. The ground state is found to exhibit striking oscillations…

Materials Science · Physics 2009-11-10 R. Saniz , B. Barbiellini , A. B. Denison , A. Bansil

We calculate the magnetization of quantum dots deviating from circular symmetry for noninteracting electrons or electrons interacting according to the Hartree approximation. For few electrons the magnetization is found to depend on their…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Ingibjorg Magnusdottir , Vidar Gudmundsson

We show here the existence of the indirect coupling of electron and magnetic or nuclear ion spins in self-assembled quantum dots mediated by electron-electron interactions. With a single localized spin placed in the center of the dot, only…

Mesoscale and Nanoscale Physics · Physics 2016-11-25 Udson C. Mendes , Marek Korkusinski , Pawel Hawrylak

Magnetic properties of two and three-dimensional clusters of quantum dots are studied with exact diagonalization of a generalized Hubbard model. We study the weak coupling limit, where the electrons interact only within a quantum dot and…

Strongly Correlated Electrons · Physics 2009-11-13 J. -P. Nikkarila , M. Koskinen , M. Manninen

The separate and combined influences of the spin-orbit and electron-electron interactions on the electron magnetization in quantum rings have been studied theoretically on the basis of the spin-density-functional theory and the Kohn-Sham…

Mesoscale and Nanoscale Physics · Physics 2013-09-23 O. S. Bauzha

A tool for the identification of the shape of quantum dots is developed. By preparing a two-electron quantum dot, the response of the low-lying excited states to a homogeneous magnetic field, i.e. their spin and parity oscillations, is…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 P. S. Drouvelis , P. Schmelcher , F. K. Diakonos

We use density-functional methods to study the effects of an external magnetic field on two-dimensional quantum dots with a rectangular hard-wall confining potential. The increasing magnetic field leads to spin polarization and formation of…

Strongly Correlated Electrons · Physics 2009-11-10 E. Räsänen , A. Harju , M. J. Puska , R. M. Nieminen

The model considered in the paper is used nowadays to describe spin dynamics of quantum dots after optical excitation. Based on the exact diagonalization of a model Hamiltonian, we solve the problems of the electron spin polarization decay…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 G. G. Kozlov

We employ the density functional Kohn-Sham method in the local spin-density approximation to study the electronic structure and magnetism of quasi one-dimensional periodic arrays of few-electron quantum dots. At small values of the lattice…

Mesoscale and Nanoscale Physics · Physics 2015-06-25 K. Karkkainen , M. Koskinen , S. M. Reimann , M. Manninen

A classical hydrodynamic approach is used to calculate the magnetoplasma excitations of two vertically coupled electron dots. The electrons are confined by different parabolic potentials in which case Kohn's theorem is no longer valid. The…

Mesoscale and Nanoscale Physics · Physics 2009-10-30 B. Partoens , A. Matulis , F. M. Peeters

We calculate the orbital magnetization of single and double quantum dots coupled both by Coulomb interaction and by electron tunneling. The electronic states of the quantum dots are calculated in a tight-binding model and the magnetization…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 A. Aldea , V. Moldoveanu , M. Nita , A. Manolescu , V. Gudmundsson , B. Tanatar

We study the development of electron-electron correlations in circular quantum dots as the density is decreased. We consider a wide range of both electron number, N<=20, and electron gas parameter, r_s<18, using the diffusion quantum Monte…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 Amit Ghosal , A. D. Guclu , C. J. Umrigar , Denis Ullmo , Harold U. Baranger

We apply quantum electrodynamical density functional theory to obtain the electronic density, the spin polarization, as well as the orbital and the spin magnetization of square periodic arrays of quantum dots or antidots subjected to the…

Mesoscale and Nanoscale Physics · Physics 2023-06-13 Vram Mughnetsyan , Vidar Gudmundsson , Nzar Rauf Abdullah , Chi-Shung Tang , Valeriu Moldoveanu , Andrei Manolescu

The description of interacting many-electron systems in external magnetic fields is considered in the framework of the optimized effective potential method extended to current-spin-density functional theory. As a case study, a…

Materials Science · Physics 2011-01-14 N. Helbig , S. Kurth , S. Pittalis , E. Räsänen , E. K. U. Gross

We consider the motion of electrons confined to a two dimensional plane with an externally applied perpendicular inhomogeneous magnetic field, both with and without a Coulomb potential. We find that as long as the magnetic field is…

Mesoscale and Nanoscale Physics · Physics 2016-08-05 C. A. Downing , M. E. Portnoi

Similar to atoms and nuclei, semiconductor quantum dots exhibit formation of shells. Predictions of magnetic behavior of the dots are often based on the shell occupancies. Thus, closed-shell quantum dots are assumed to be inherently…

Mesoscale and Nanoscale Physics · Physics 2011-06-14 R. Oszwałdowski , I. Žutić , A. G. Petukhov

We suggest a new spin orientation mechanism for localized electrons: $dynamic~electron~spin~polarization~provided~by~nuclear~spin~fluctuations$. The angular momentum for the electrons is gained from the nuclear spin system via the hyperfine…

Mesoscale and Nanoscale Physics · Physics 2020-10-14 D. S. Smirnov , T. S. Shamirzaev , D. R. Yakovlev , M. Bayer

Magnetic field usually leads to a polarization of electron spins. It is shown that in a system of {\em strongly interacting} particles applying magnetic field may lead to an opposite effect -- depolarization of electron spins. Results of…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 S. A. Mikhailov , N. A. Savostianova

On a basis of extensive analytical and numerical studies we show that a linear-polarized microwave field creates a stationary magnetization in mesoscopic ballistic quantum dots with two-dimensional electron gas being at a thermal…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 A. D. Chepelianskii , D. L. Shepelyansky

Hyperfine interaction of electron spins with nuclear spins, in coupled double quantum dots is studied. Results of successive electron spin measurements exhibit bunching due to correlations induced via the nuclear spins. Further nuclear…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Ozgur Cakir , Toshihide Takagahara
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