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arXiv · 1009.2116

Antiferromagnetic Critical Fluctuations in BaFe$_2$As$_2$

Stephen D. Wilson·Z. Yamani·C. R. Rotundu·B. Freelon·P. N. Valdivia·E. Bourret-Courchesne·J. W. Lynn·Songxue Chi·Tao Hong·R. J. Birgeneau
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Abstract

Magnetic correlations near the magneto-structural phase transition in the bilayer iron pnictide parent compound, BaFe$_2$As$_2$, are measured. In close proximity to the antiferromagnetic phase transition in BaFe$_2$As$_2$, a crossover to three dimensional critical behavior is anticipated and has been preliminarily observed. Here we report complementary measurements of two-dimensional magnetic fluctuations over a broad temperature range about T$_N$. The potential role of two-dimensional critical fluctuations in the magnetic phase behavior of BaFe$_2$As$_2$ and their evolution near the anticipated crossover to three dimensional critical behavior and long-range order are discussed.

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Stephen D. Wilson, Z. Yamani, C. R. Rotundu, B. Freelon, P. N. Valdivia, E. Bourret-Courchesne, J. W. Lynn, Songxue Chi, Tao Hong, R. J. Birgeneau. 2010-09-10. Antiferromagnetic Critical Fluctuations in BaFe$_2$As$_2$. https://doi.org/10.1103/physrevb.82.144502

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