Correlation and spin polarization in quantum dots: Local spin density functional theory revisited
(2005) In International Journal of Quantum Chemistry 105(6). p.817-825- Abstract
- Using quantum dot artificial atoms as a simple toy model, we reflect on the question of whether spin density functional theory (SDFT) can accurately describe correlation effects in low-dimensional fermion systems. Different expressions for the local density approximation of the exchange-correlation energy for the two-dimensional electron gas, such as the much-used functional of Tanatar and Ceperley, and the recent suggestion by Attaccalite et al., are compared with the results of a numerical diagonalization of the many-body Hamiltonian matrix in the limit of small electron numbers. For systems with degeneracies, as shown in the present work for the example of a spin triplet with S = 1, the direct comparison with configuration interaction... (More)
- Using quantum dot artificial atoms as a simple toy model, we reflect on the question of whether spin density functional theory (SDFT) can accurately describe correlation effects in low-dimensional fermion systems. Different expressions for the local density approximation of the exchange-correlation energy for the two-dimensional electron gas, such as the much-used functional of Tanatar and Ceperley, and the recent suggestion by Attaccalite et al., are compared with the results of a numerical diagonalization of the many-body Hamiltonian matrix in the limit of small electron numbers. For systems with degeneracies, as shown in the present work for the example of a spin triplet with S = 1, the direct comparison with configuration interaction (Cl) methods demonstrates that the spin representation of SDFT may, under certain circumstances, produce artificial energy splittings between states that belong to the same spin multiplet. For a singlet ground state with S = S = 0, however, the correlation functions of the Cl solutions confirm the spin-density wave states found earlier within the SDFT method. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/214225
- author
- Borgh, Magnus LU ; Toreblad, Maria LU ; Koskinen, M ; Manninen, M ; Åberg, Sven LU and Reimann, Stephanie LU
- organization
- publishing date
- 2005
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- spin symmetry, calculations, configuration interaction, quantum dots, density functional method, spin-density waves
- in
- International Journal of Quantum Chemistry
- volume
- 105
- issue
- 6
- pages
- 817 - 825
- publisher
- John Wiley & Sons Inc.
- external identifiers
-
- wos:000233063100030
- scopus:30544454965
- ISSN
- 0020-7608
- DOI
- 10.1002/qua.20802
- language
- English
- LU publication?
- yes
- additional info
- The information about affiliations in this record was updated in December 2015. The record was previously connected to the following departments: Mathematical Physics (Faculty of Technology) (011040002)
- id
- fefd0801-d499-4cc1-a459-66662f0a27ba (old id 214225)
- date added to LUP
- 2016-04-01 12:13:42
- date last changed
- 2022-01-27 00:44:07
@article{fefd0801-d499-4cc1-a459-66662f0a27ba, abstract = {{Using quantum dot artificial atoms as a simple toy model, we reflect on the question of whether spin density functional theory (SDFT) can accurately describe correlation effects in low-dimensional fermion systems. Different expressions for the local density approximation of the exchange-correlation energy for the two-dimensional electron gas, such as the much-used functional of Tanatar and Ceperley, and the recent suggestion by Attaccalite et al., are compared with the results of a numerical diagonalization of the many-body Hamiltonian matrix in the limit of small electron numbers. For systems with degeneracies, as shown in the present work for the example of a spin triplet with S = 1, the direct comparison with configuration interaction (Cl) methods demonstrates that the spin representation of SDFT may, under certain circumstances, produce artificial energy splittings between states that belong to the same spin multiplet. For a singlet ground state with S = S = 0, however, the correlation functions of the Cl solutions confirm the spin-density wave states found earlier within the SDFT method.}}, author = {{Borgh, Magnus and Toreblad, Maria and Koskinen, M and Manninen, M and Åberg, Sven and Reimann, Stephanie}}, issn = {{0020-7608}}, keywords = {{spin symmetry; calculations; configuration interaction; quantum dots; density functional method; spin-density waves}}, language = {{eng}}, number = {{6}}, pages = {{817--825}}, publisher = {{John Wiley & Sons Inc.}}, series = {{International Journal of Quantum Chemistry}}, title = {{Correlation and spin polarization in quantum dots: Local spin density functional theory revisited}}, url = {{http://dx.doi.org/10.1002/qua.20802}}, doi = {{10.1002/qua.20802}}, volume = {{105}}, year = {{2005}}, }