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arXiv · 2401.07026

Magnetic effects of non-magnetic impurities in gapped short-range resonating valence bond spin liquids

Md Zahid Ansari·Kedar Damle
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Abstract

We study the effect of a small density $n_v$ of quenched non-magnetic impurities, i.e. vacancy disorder, in gapped short-range resonating valence bond (RVB) spin liquid states and valence bond solid (VBS) states of quantum magnets. We argue that a large class of short-range RVB liquids are stable at small $n_v$ on the kagome lattice, while the corresponding states on triangular, square, and honeycomb lattices are unstable at any nonzero $n_v$ due to the presence of emergent vacancy-induced local moments. In contrast, VBS states are argued to be generically unstable (independent of lattice geometry) at nonzero $n_v$ due to such a local-moment instability. Our arguments rely in part on an analysis of the statistical mechanics of maximally-packed dimer covers of the diluted lattice, and are fully supported by our computational results on $O(N)$ symmetric designer Hamiltonians.

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Md Zahid Ansari, Kedar Damle. 2024-01-13. Magnetic effects of non-magnetic impurities in gapped short-range resonating valence bond spin liquids. https://doi.org/10.1103/physrevlett.132.226504

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