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arXiv · 2212.09554

Projective symmetry group classification of Abrikosov fermion mean-field ansätze on the square-octagon lattice

Atanu Maity·Francesco Ferrari·Ronny Thomale·Saptarshi Mandal·Yasir Iqbal
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Abstract

We perform a projective symmetry group (PSG) classification of symmetric quantum spin liquids with different gauge groups on the square-octagon lattice. Employing the Abrikosov fermion representation for spin-$1/2$, we obtain $32$ $SU(2)$, $1808$ $U(1)$ and $384$ $\mathbb{Z}_{2}$ algebraic PSGs. Constraining ourselves to mean-field parton ansätze with short-range amplitudes, the classification reduces to a limited number, with 4 $SU(2)$, 24 $U(1)$ and 36 $\mathbb{Z}_{2}$, distinct phases. We discuss their ground state properties and spinon dispersions within a self-consistent treatment of the Heisenberg Hamiltonian with frustrating couplings.

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Atanu Maity, Francesco Ferrari, Ronny Thomale, Saptarshi Mandal, Yasir Iqbal. 2023-04-27. Projective symmetry group classification of Abrikosov fermion mean-field ansätze on the square-octagon lattice. https://doi.org/10.1103/physrevb.107.134438

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