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A low-dimensional spin S = 1/2 system at the quantum critical limit: Na2V2O7

J. L. Gavilano·D. Rau·S. Mushkolaj·H. R. Ott·P. Millet·F. Mila
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Abstract

We report the results of measurements of the dc-susceptibility and the 23Na-NMR response of Na2V2O7, a recently synthesized, non metallic low dimensional spin system. Our results indicate that upon reducing the temperature to below 100 K, the V^{4+} moments are gradually quenched, leaving only one moment out of 9 active. The NMR data reveal a phase transition at very low temperatures. With decreasing applied field H, the critical temperature shifts towards T = 0 K, suggesting that Na2V2O7 may be regarded as an insulator reaching a quantum critical point at H = 0.

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J. L. Gavilano, D. Rau, S. Mushkolaj, H. R. Ott, P. Millet, F. Mila. 2002-10-24. A low-dimensional spin S = 1/2 system at the quantum critical limit: Na2V2O7. https://doi.org/10.1103/physrevlett.90.167202

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