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Random Frustration in two-dimensional spin-1/2 Heisenberg antiferromagnet

J. P. Rodriguez·J. Bonca·J. Ferrer
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Abstract

The square lattice spin-1/2 antiferromagnet containing a dilute concentration, $δ$, of randomly placed ferromagnetic nearest-neighbor bonds is studied at low-temperature via non-linear $σ$-model techniques and by exact diagonalization. We generally find that long-range N\' eel order is destroyed above a critical strength in the defective ferromagnetic exchange coupling-constant given by $|K_c|/J\sim δ^{-1/2}$. We also observe large statistical fluctuations both in the spin-stiffness and in the antiferromagnetic structure-factor near this critical point, suggesting the onset of a spin-glass phase.

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J. P. Rodriguez, J. Bonca, J. Ferrer. 1994-11-02. Random Frustration in two-dimensional spin-1/2 Heisenberg antiferromagnet. https://doi.org/10.1103/physrevb.51.3616

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