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arXiv · 1506.06109

Effective Hamiltonian for a Half-filled Asymmetric Ionic Hubbard Chain with Alternating On-site Interaction

Inna Grusha·Mikheil Menteshashvili·George I. Japaridze
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Abstract

We derive an effective spin Hamiltonian for the one-dimensional half-filled asymmetric ionic Hubbard model with alternating on-site interaction in the limit of strong repulsion. It is shown that the effective Hamiltonian is that of a spin $S=1/2$ anisotropic $XXZ$ Heisenberg chain with alternating next-nearest-neighbor and three-spin couplings in the presence of a uniform and a staggered magnetic field.

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Inna Grusha, Mikheil Menteshashvili, George I. Japaridze. 2015-06-19. Effective Hamiltonian for a Half-filled Asymmetric Ionic Hubbard Chain with Alternating On-site Interaction. https://doi.org/10.1142/s0217979215502604

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