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arXiv · 1610.02053

Biorthogonal projected energies of a Gutzwiller similarity transformed Hamiltonian

Jacob M. Wahlen-Strothman·Gustavo E. Scuseria
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Abstract

We present a method incorporating biorthogonal orbital-optimization, symmetry projection, and double-occupancy screening with a non-unitary similarity transformation generated by the Gutzwiller factor $ n_{i\uparrow}n_{i\downarrow}$, and apply it to the Hubbard model. Energies are calculated with mean-field computational scaling with high-quality results comparable to coupled cluster singles and doubles. This builds on previous work performing similarity transformations with more general, two-body Jastrow-style correlators. The theory is tested on two-dimensional lattices ranging from small systems into the thermodynamic limit and is compared to available reference data.

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Jacob M. Wahlen-Strothman, Gustavo E. Scuseria. 2016-10-06. Biorthogonal projected energies of a Gutzwiller similarity transformed Hamiltonian. https://doi.org/10.1088/0953-8984/28/48/485502

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