Electron correlations in two-dimensional small quantum dots

Abstract

We consider circular and elliptic quantum dots with parabolic external confinement, containing 0 - 22 electrons and with values of r_s in the range 0 < r_s < 3. We perform restricted and unrestricted Hartree-Fock calculations, and further take into account electron correlations using second-order perturbation theory. We demonstrate that in many cases correlations qualitatively change the spin structure of the ground state from that obtained under Hartree-Fock and spin-density-functional calculations. In some cases the correlation effects destroy Hund's rule. We also demonstrate that the correlations destroy static spin-density waves observed in Hartree-Fock and spin-density-functional calculations.

arXiv comment11 pages, 9 figures. This replacement contains new content. Results have been recalculated for dots with zero effective thickness (true 2D). For 6 electrons, results have been compared with configuration interaction results from the literature

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Cited by in corpus (7)

• Two-electron entanglement in elliptically deformed quantum dots
• Many-Body perturbation theory calculations on circular quantum dots
• Performance of the coupled cluster singles and doubles method on two-dimensional quantum dots
• Correlation energy of anisotropic quantum dots
• Interacting spin-droplets and magnetic properties of a low-density two-dimensional electron gas
• Phase Separation in Two-Dimensional Electron Systems: Experimental View
• Coupled cluster theory for the ground and excited states of two dimensional quantum dots