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arXiv · 2110.07442

Hubbard model for spin-1 Haldane chains

G. Catarina·J. Fernández-Rossier
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Abstract

The Haldane phase for antiferromagnetic spin-1 chains is a celebrated topological state of matter, featuring gapped excitations and fractional spin-1/2 edge states. Here, we provide numerical evidence that this phase can be realized with a Hubbard model at half filling, where each $s=1$ spin is stored in a four-site fermionic structure. We find that the noninteracting limit of our proposed model describes a one-dimensional topological insulator, and we conjecture it to be adiabatically connected to the Haldane phase. Our work suggests a route to build spin-1 networks using Hubbard model quantum simulators.

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G. Catarina, J. Fernández-Rossier. 2021-10-14. Hubbard model for spin-1 Haldane chains. https://doi.org/10.1103/physrevb.105.l081116

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