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Effective Hamiltonian for a Half-filled Hubbard Chain with Alternating On-site Interactions

Paata Kakashvili·George I. Japaridze
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Abstract

We derive an effective spin Hamiltonian for the one-dimensional half-filled Alternating Hubbard model in the limit of strong on-site repulsion. We show that the effective Hamiltonian is a spin $S=1/2$ Heisenberg chain with asymmetric next-nearest-neighbor (nnn) exchange.

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Paata Kakashvili, George I. Japaridze. 2004-05-04. Effective Hamiltonian for a Half-filled Hubbard Chain with Alternating On-site Interactions. https://doi.org/10.1088/0953-8984%2F16%2F32%2F017

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