Dieter Vollhardt

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Dieter Vollhardt (born September 8, 1951) is a German physicist and Professor of Theoretical Physics at the University of Augsburg.

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Scientific work

Vollhardt is one of the founders of the Dynamical Mean-Field Theory (DMFT) for strongly correlated materials such as transition metals (e.g. iron or vanadium) and their oxides, i.e. materials with electrons in open d- and f-shells. The properties of these systems are determined by the Coulomb repulsion between the electrons which makes these electrons strongly correlated. The repulsion has the tendency to localize electrons. This leads to a multitude of phenomena such as the Mott-Hubbard metal insulator transition. Conventional band theory or density functional theory cannot describe these systems adequately. In 1989 Vollhardt and his doctoral student Walter Metzner introduced electronic models with local interaction (Hubbard model) on a lattice with infinitely many nearest neighbors, [1] which Gabriel Kotliar and Antoine Georges [2] then developed into the DMFT. [3] The DMFT may be viewed as a self-consistent, field-theoretical generalization of a quantum impurity model by Philip W. Anderson, where the mean-field describes the coupling of the impurity to an "electronic bath".

DMFT provides an exact description of the quantum dynamics of correlated lattice systems with local interaction, but neglects spatial correlations. It has provided fundamental insights into the properties of correlated electronic systems. The combination of the DMFT with material-specific approaches, such as the "Local Density Approximation" (LDA) to the density functional theory, led to a new computational scheme, often referred to as LDA+DMFT, for the investigation of strongly correlated materials. [4] [5] [6]

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References

  1. Metzner, Walter (1989). "Correlated Lattice Fermions in d = ∞ Dimensions". Physical Review Letters. 62 (3): 324–327. Bibcode:1989PhRvL..62..324M. doi:10.1103/PhysRevLett.62.324. PMID   10040203.
  2. Georges, Antoine (1992). "Hubbard model in infinite dimensions". Physical Review B. 45 (12): 6479–6483. Bibcode:1992PhRvB..45.6479G. doi:10.1103/PhysRevB.45.6479. PMID   10000408.
  3. Georges, Antoine (1996). "Dynamical mean-field theory of strongly correlated fermion systems and the limit of infinite dimensions". Reviews of Modern Physics. 68 (1): 13–125. Bibcode:1996RvMP...68...13G. doi:10.1103/RevModPhys.68.13.
  4. K. Held, I. A. Nekrasov, G. Keller, V. Eyert, N. Blümer, A. K. McMahan, R. T. Scalettar, T. Pruschke, V. I. Anisimov, D. Vollhardt, Psi-k Newsletter No. 56 (April 2003), p. 65 Archived 2006-10-09 at the Wayback Machine
  5. Georges, Antoine (1996). "Dynamical mean-field theory of strongly correlated fermion systems and the limit of infinite dimensions". Reviews of Modern Physics. 68 (1): 13–125. Bibcode:1996RvMP...68...13G. doi:10.1103/RevModPhys.68.13.
  6. The LDA+DMFT approach to strongly correlated materials Archived 2013-10-05 at the Wayback Machine , Lecture Notes of the Autumn School 2011 Hands-on LDA+DMFT, Editors: E. Pavarini, E. Koch, D. Vollhardt, A. Lichtenstein, Forschungszentrum Jülich (2011)