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Phase diagram regions deduced for strongly correlated systems via unitary transformation

E Kovacs·Zs. Gulacsi
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Abstract

From known phase diagram regions of different model Hamiltonians describing strongly correlated systems we deduced new domains of the ground state phase diagram of the same model by an unitary transformation. Different types of extended Hubbard Hamiltonians were used for the starting point and the existence of new stable spin-density wave, charge-density wave, ferromagnetic state and a paramagnetic insulator is demonstrated. The used procedure itself is dimension independent.

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E Kovacs, Zs. Gulacsi. 2001-04-09. Phase diagram regions deduced for strongly correlated systems via unitary transformation. https://doi.org/10.1080/13642810108221988

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