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arXiv · 2308.07965

A Kitaev-type spin liquid on a quasicrystal

M. A. Keskiner·O. Erten·M. Ö. Oktel
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Abstract

We develop an exactly solvable model with Kitaev-type interactions and study its phase diagram on the dual lattice of the quasicrystalline Ammann-Beenker lattice. Our construction is based on the $\Gamma$-matrix generalization of the Kitaev model and utilizes the cut-and-project correspondence between the four-dimensional simple cubic lattice and the Ammann-Beenker lattice to designate four types of bonds. We obtain a rich phase diagram with gapped (chiral and abelian) and gapless spin liquid phases via Monte Carlo simulations and variational analysis. We show that the ground state can be further tuned by the inclusion of an onsite term that selects 21 different vison configurations while maintaining the integrability of the model. Our results highlight the rich physics at the intersection of quasicrystals and quantum magnetism.

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M. A. Keskiner, O. Erten, M. Ö. Oktel. 2023-08-15. A Kitaev-type spin liquid on a quasicrystal. https://doi.org/10.1103/physrevb.108.104208

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