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Spin Correlations and Magnetic Order in Nonsuperconducting Nd_{2-x}Ce_xCuO_{4\pmδ}

P. K. Mang·O. P. Vajk·A. Arvanitaki·J. W. Lynn·M. Greven
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Abstract

We report quantitative neutron scattering measurements of the evolution with doping of the Néel temperature, the antiferromagnetic correlations, and the ordered moment of as-grown, nonsuperconducting Nd_{2-x}Ce_xCuO_{4\pmδ} ($0 \le x \le 0.18$). The instantaneous correlation length can be effectively described by our quantum Monte Carlo calculations for the randomly site-diluted nearest-neighbor spin-1/2 square-lattice Heisenberg antiferromagnet. However, quantum fluctuations have a stronger effect on the ordered moment, which decreases more rapidly than for the quenched-disorder model.

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P. K. Mang, O. P. Vajk, A. Arvanitaki, J. W. Lynn, M. Greven. 2004-08-24. Spin Correlations and Magnetic Order in Nonsuperconducting Nd_{2-x}Ce_xCuO_{4\pmδ}. https://doi.org/10.1103/physrevlett.93.027002

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