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arXiv · 0810.0784

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

J. Rotureau·N. Michel·W. Nazarewicz·M. Ploszajczak·J. Dukelsky
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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 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.

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J. Rotureau, N. Michel, W. Nazarewicz, M. Ploszajczak, J. Dukelsky. 2008-10-04. Density matrix renormalization group approach to two-fluid open many-fermion systems. https://doi.org/10.1103/physrevc.79.014304

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