Self-Consistent Effective Hamiltonian Theory for Fermionic Many Body Systems

Xindong Wang; Hai-Ping Cheng

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arXiv · 1910.12136

Self-Consistent Effective Hamiltonian Theory for Fermionic Many Body Systems

Xindong Wang·Hai-Ping Cheng

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Abstract

Using a separable many-body variational wavefunction, we formulate a self-consistent effective Hamiltonian theory for fermionic many-body system. The theory is applied to the two-dimensional Hubbard model as an example to demonstrate its capability and computational effectiveness. Most remarkably for the Hubbard model in 2-d, a highly unconventional quadruple-fermion non-Cooper-pair order parameter is discovered.

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Xindong Wang, Hai-Ping Cheng. 2019-10-26. Self-Consistent Effective Hamiltonian Theory for Fermionic Many Body Systems. https://arxiv.org/abs/1910.12136

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