Erlangen 2018 – wissenschaftliches Programm
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Q: Fachverband Quantenoptik und Photonik
Q 6: Quantum Information (Concepts and Methods) I
Q 6.7: Vortrag
Montag, 5. März 2018, 12:15–12:30, K 1.019
Natural extensions of Hartree-Fock based on extremal one-particle information — •Carlos L. Benavides-Riveros1 and Christian Schilling2 — 1Institut für Physik, Martin-Luther-Universität Halle-Wittenberg, 06120 Halle, Germany — 2Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom
One-particle density matrices are compatible with pure N-fermion quantum states whenever their spectra (natural occupation numbers) lie in the polytope defined by the generalized Pauli constraints. We characterize existing and propose novel extensions of the Hartree-Fock ansatz by referring to the different facets of that polytope. Moreover, we derive a quantitative relation between the accuracy of those variational ansatzes and the distance of the exact ground state's occupation number vector to the respective polytope facets. In an extensive numerical study those ansatzes are tested and we explain how a geometrical hierarchy of the polytope allows one to systematically recover all static correlation energy.