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arXiv · 2607.15813

Thermal Order by Disorder in Resonating-Valence Bond States on the Checkerboard Lattice

Giorgi Gogaberishvili·Nika Kurdadze·Kirill Shtengel
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Abstract

We derive a local spin-1/2 Hamiltonian with a resonating valence bond ground state on the checkerboard lattice. The state is characterized by the exponential decay of singlet-singlet correlations, whereas dimer-dimer correlations decay with a power law in the corresponding Quantum Dimer model. This observation leads to a novel mechanism for thermal Order by Disorder whereby thermal decoherence suppresses destructive quantum interference between different contributions to the correlations in the ground state and results in a qualitatively different, quasi-long-range ordered mixed state.

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Giorgi Gogaberishvili, Nika Kurdadze, Kirill Shtengel. 2026-07-17. Thermal Order by Disorder in Resonating-Valence Bond States on the Checkerboard Lattice. https://arxiv.org/abs/2607.15813

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