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arXiv:0810.0784 · Physical Review C

Density matrix renormalization group approach to two-fluid open many-fermion systems

J. Rotureau, N. Michel, Witold Nazarewicz, Marek Płoszajczak, J. Dukelsky

Published Jan 15, 2009• 39 citations
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Abstract

We have extended the density matrix renormalization group (DMRG) approach to two-fluid open many-fermion systems governed by complex-symmetric Hamiltonians. The applications are carried out for three- and four-nucleon (proton-neutron) systems within the Gamow shell model (GSM) in the complex-energy plane. We study necessary and sufficient conditions for the GSM+DMRG method to yield the correct ground-state eigenvalue and discuss different truncation schemes within the DMRG. The proposed approach will enable configuration interaction studies of weakly bound and unbound strongly interacting complex systems, which, because of a prohibitively large size of Fock space, cannot be treated by means of the direct diagonalization.

DOI
10.1103/physrevc.79.014304

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