Dresden 2009 – wissenschaftliches Programm
O 24.3: Vortrag
Dienstag, 24. März 2009, 15:30–15:45, SCH A01
Correlation energy of two-dimensional systems: toward non-empirical and universal modeling — •S. Pittalis1, 3, E. Rasanen2, 3, C. Proetto1, 3, and E.K.U. Gross1, 3 — 1Institut fuer Theoretische Physik, Freie Universitaet Berlin, Arnimallee 14, D-14195 Berlin, Germany — 2Nanoscience Center, Department of Physics, University of Jyvaskyla, FIN-40014 Jyvaskyla, Finland — 3European Theoretical Spectroscopy Facility (ETSF)
The capability of density-functional theory to deal with the ground-state of correlated systems depends on the accuracy of functionals developed for the exchange and correlation energies. Most of the approximations developed so far have focused on three-dimensional systems. Such efforts for two-dimensional (2D) systems have been relatively scarce despite the rapidly increasing experimental and theoretical interest in 2D structures such as semiconductor heterostructures, quantum-Hall systems, graphene, and various types of quantum dots. Here we derive a correlation-energy functional for 2D systems by modeling the correlation-hole functions in such a way that they satisfy a set of exact properties. We find very encouraging results for a wide range of correlation energies covering several few-electron quantum dots with and without external magnetic field, having different spin-polarizations and current densities.