A v0-representability issue in lattice ensemble-DFT and its signature in lattice TDDFT
(2018) In European Physical Journal B 91. p.1-8- Abstract
- We study a small Anderson-impurity cluster using lattice density functional methods, and try to
determine the exact exchange-correlation (XC) potential via reverse engineering. In doing so we nd singlet{
triplet degenerate interacting ground states which cannot be v0-represented in an ensemble-DFT sense. We
also nd that it is possible to represent a triplet ground state as a pure state, but not the singlet. We further investigate this behavior within time-dependent density-functional theory. Starting from a v0-representableground state and entering the degeneracy region via a time-dependent perturbation, we determine via reverse-engineering the time-dependent XC potential for progressively slower perturbations. This analysis... (More) - We study a small Anderson-impurity cluster using lattice density functional methods, and try to
determine the exact exchange-correlation (XC) potential via reverse engineering. In doing so we nd singlet{
triplet degenerate interacting ground states which cannot be v0-represented in an ensemble-DFT sense. We
also nd that it is possible to represent a triplet ground state as a pure state, but not the singlet. We further investigate this behavior within time-dependent density-functional theory. Starting from a v0-representableground state and entering the degeneracy region via a time-dependent perturbation, we determine via reverse-engineering the time-dependent XC potential for progressively slower perturbations. This analysis shows that, even in a constant external eld, the XC potential must retain a time-oscillating pattern to ensure a density constant in time, a hint of the underlying representability issue in the ground state. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/8f25a90c-1f3e-44da-8dde-00bbbc382762
- author
- Rössler, Thomas LU ; Verdozzi, Claudio LU and Almbladh, Carl-Olof LU
- organization
- publishing date
- 2018-10-01
- type
- Contribution to journal
- publication status
- published
- subject
- in
- European Physical Journal B
- volume
- 91
- article number
- 219
- pages
- 8 pages
- publisher
- Springer
- external identifiers
-
- scopus:85057242197
- ISSN
- 1434-6028
- DOI
- 10.1140/epjb/e2018-90205-7
- language
- English
- LU publication?
- yes
- id
- 8f25a90c-1f3e-44da-8dde-00bbbc382762
- date added to LUP
- 2019-05-16 10:58:02
- date last changed
- 2024-01-15 19:53:36
@article{8f25a90c-1f3e-44da-8dde-00bbbc382762, abstract = {{We study a small Anderson-impurity cluster using lattice density functional methods, and try to<br/>determine the exact exchange-correlation (XC) potential via reverse engineering. In doing so we nd singlet{<br/>triplet degenerate interacting ground states which cannot be v0-represented in an ensemble-DFT sense. We<br/>also nd that it is possible to represent a triplet ground state as a pure state, but not the singlet. We further investigate this behavior within time-dependent density-functional theory. Starting from a v0-representableground state and entering the degeneracy region via a time-dependent perturbation, we determine via reverse-engineering the time-dependent XC potential for progressively slower perturbations. This analysis shows that, even in a constant external eld, the XC potential must retain a time-oscillating pattern to ensure a density constant in time, a hint of the underlying representability issue in the ground state.}}, author = {{Rössler, Thomas and Verdozzi, Claudio and Almbladh, Carl-Olof}}, issn = {{1434-6028}}, language = {{eng}}, month = {{10}}, pages = {{1--8}}, publisher = {{Springer}}, series = {{European Physical Journal B}}, title = {{A v0-representability issue in lattice ensemble-DFT and its signature in lattice TDDFT}}, url = {{http://dx.doi.org/10.1140/epjb/e2018-90205-7}}, doi = {{10.1140/epjb/e2018-90205-7}}, volume = {{91}}, year = {{2018}}, }