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Saarikoski, Henri; Räsänen, E.; Siljamäki, S.; Harju, Ari; Puska, Martti J.; Nieminen, Risto M.

doi:10.1007/s10051-002-8962-8

Cited by 36 publications

(53 citation statements)

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“…Ref. 25) that include spin polarization explicitly. We have, however, checked that for the quantities in which we are interested here, this new functional introduces only minor modifications; we shall therefore use Tanatar-Ceperley's form for our discussion.…”

Section: The Screened Interaction In the Local Density Approximamentioning

confidence: 99%

Landau Fermi-liquid picture of spin density functional theory: Strutinsky approach to quantum dots

et al. 2004

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We analyze the ground state energy and spin of quantum dots obtained from spin density functional theory (SDFT) calculations. First, we introduce a Strutinsky-type approximation, in which quantum interference is treated as a correction to a smooth Thomas-Fermi description. For large irregular dots, we find that the secondorder Strutinsky expressions have an accuracy of about 5 percent compared to the full SDFT and capture all the qualitative features. Second, we perform a random matrix theory/random plane wave analysis of the Strutinsky SDFT expressions. The results are statistically similar to the SDFT quantum dot statistics. Finally, we note that the second-order Strutinsky approximation provides, in essence, a Landau Fermi liquid picture of spin density functional theory. For instance, the leading term in the spin channel is simply the familiar exchange constant. A direct comparison between SDFT and the perturbation theory derived "universal Hamiltonian" is thus made possible.

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Section: The Screened Interaction In the Local Density Approximamentioning

confidence: 99%

Landau Fermi-liquid picture of spin density functional theory: Strutinsky approach to quantum dots

et al. 2004

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“…(Various parameterizations for ǫ xc for strong fields ν < 1 as well as different interpolation schemes between the low and the strong fields are reviewed in Refs. 24,29 ). Note that the DFT was used for the description of the spin polarization of the edge states in quantum wires in the integer Hall regime within ThomasFermi approximation 8 , as well as for the treatment of spinless edge states in the Kohn-Sham scheme based on the solution of the Schrödinger equation 14 .…”

Section: Approximationsmentioning

confidence: 99%

Spin polarization of edge states and the magnetosubband structure in quantum wires

2006

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We provide a quantitative description of the structure of edge states in split-gate quantum wires in the integer quantum Hall regime. We develop an effective numerical approach based on the Green's function technique for the self-consistent solution of Schrödinger equation where electron-and spin interactions are included within the density functional theory in the local spin density approximation. The major advantage of this technique is that it can be directly incorporated into magnetotransport calculations, because it provides the self-consistent eigenstates and wave vectors at a given energy, not at a given wavevector (as conventional methods do). We use the developed method to calculate the subband structure and propagating states in the quantum wires in perpendicular magnetic field starting with a geometrical layout of the wire. We discuss how the spin-resolved subband structure, the current densities, the confining potentials, as well as the spin polarization of the electron and current densities evolve when an applied magnetic field varies. We demonstrate that the exchange and correlation interactions dramatically affect the magnetosubbands in quantum wires bringing qualitatively new features in comparison to a widely used model of spinless electrons in Hartree approximation. I. INRODUCTIONTransport properties of quantum dots, antidots and related structures are affected by the nature of currentcarrying states in the leads connecting these structures to electron reservoirs. In sufficiently high magnetic fields the current-carrying states are the edge states propagating in a close vicinity to the sample boundaries 1 . A detailed information on the structure of the edge states represent a key to the understanding of various features of the magnetotransport in the quantum Hall regime.A quantitative description of the edge states for the case of the gate-induced confinement of the highmobility two-dimensional electron gas (2DEG) was given by Chklovskii et al.2 , who provided an analytical solution for the positions and widths of the compressible and incompressible strips arising in the 2DEG due to the electrostatic screening. In the compressible regions, the Landau bands are pinned at the Fermi energy E F . This leads to a metallic behavior when the electron density is redistributed (compressed) to keep the electrostatic potential constant. In the incompressible regions, where the Fermi energy lies in the Landau gaps, all the levels below E F are completely filled and hence the electron density is constant (which is consistent with the behavior of the incompressible liquid).A number of studies addressing the problem of electron-electron interaction in quantum wires beyond the electrostatic treatment of the edge states of Chklovskii et al.2 have been reported during the recent decade 3,4,5,6,7,8,9,10,11,12,13,14 . The many-body aspects of the problem have been included within ThomasFermi 3 , Hartree-Fock 4,5,6 , screened Hartree-Fock 7 , and the density functional theory 8,9 . The full quantummechanical calc...

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“…19 As another valid approximation, we neglect the dependence of the exchange and correlation on the vorticity. 20 The exchange and correlation energies and potentials are calculated using the 2D local spin-density approximation, for which we use the QMC parametrization of the correlation energy by Attaccalite et al…”

Section: B Density-functional Theorymentioning

confidence: 99%

Pfaffian and fragmented states atν=52in quantum Hall droplets

et al. 2008

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When a gas of electrons is confined to two dimensions, application of a strong magnetic field may lead to startling phenomena such as emergence of electron pairing. According to a theory this manifests itself as appearance of the fractional quantum Hall effect with a quantized conductivity at an unusual half-integer ν = 5 2Landau level filling. Here we show that similar electron pairing may occur in quantum dots where the gas of electrons is trapped by external electric potentials into small quantum Hall droplets. However, we also find theoretical and experimental evidence that, depending on the shape of the external potential, the paired electron state can break down, which leads to a fragmentation of charge and spin densities into incompressible domains. The fragmentation of the quantum Hall states could be an issue in the proposed experiments that aim to probe for non-abelian quasi-particle characteristics of the ν = 5 2 quantum Hall state.

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Cited by 36 publications

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Landau Fermi-liquid picture of spin density functional theory: Strutinsky approach to quantum dots

Landau Fermi-liquid picture of spin density functional theory: Strutinsky approach to quantum dots

Spin polarization of edge states and the magnetosubband structure in quantum wires

Pfaffian and fragmented states atν=52in quantum Hall droplets

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