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Effective Sublattice Magnetization and Neel Temperature in Quantum Antiferromagnets

Eduardo C. Marino·Marcello B. Silva Neto
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Abstract

We present an analytic expression for the finite temperature effective sublattice magnetization which would be detected by inelastic neutron scattering experiments performed on a two-dimensional square-lattice quantum Heisenberg antiferromagnets with short range Néel order. Our expression, which has no adjustable parameters, is able to reproduce both the qualitative behaviour of the phase diagram $M(T)xT$ and the experimental values of the Néel temperature $T_{N}$ for either doped YBa$_{2}$Cu$_{3}$O$_{6.15}$ and stoichiometric La$_{2}$CuO$_{4}$ compounds. Finally, we remark that by incorporating frustration and 3D effects as perturbations is sufficient to explain the deviation of the experimental data from our theoretical curves.

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Eduardo C. Marino, Marcello B. Silva Neto. 2000-03-13. Effective Sublattice Magnetization and Neel Temperature in Quantum Antiferromagnets. https://doi.org/10.1103/physrevb.62.142

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