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arXiv · 0907.2936

Anisotropic thermal expansion of AEFe2As2 (AE = Ba, Sr, Ca) single crystals

Sergey L. Bud'ko·Ni Ni·Paul C. Canfield
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Abstract

We report anisotropic thermal expansion of the parent, AEFe2As2 (AE = Ba, Sr, and Ca), compounds. Above the structural/antiferromagnetic phase transition anisotropy of the thermal expansion coefficients is observed, with the coefficient along the a-axis being significantly smaller than the coefficient for the c-axis. The high temperature (200 K < T < 300 K) coefficients themselves have similar values for the compounds studied. The sharp anomalies associated with the structural/antiferromagnetic phase transitions are clearly seen in the thermal expansion measurements. For all three pure compounds the "average" a-value increases and the c-lattice parameter decreases on warming through the transition with the smallest change in the lattice parameters observed for SrFe2As2. The data are in general agreement with the literature data from X-ray and neutron diffraction experiments.

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Sergey L. Bud'ko, Ni Ni, Paul C. Canfield. 2009-07-16. Anisotropic thermal expansion of AEFe2As2 (AE = Ba, Sr, Ca) single crystals. https://doi.org/10.1080/14786430903325041

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