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arXiv · 1008.2635

Thermal expansion of the superconducting ferromagnet UCoGe

A. Gasparini·Y. K. Huang·J. Hartbaum·H. von Lohneysen·A. de Visser
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Abstract

We report measurements of the coefficient of linear thermal expansion, $\alpha (T)$, of the superconducting ferromagnet UCoGe. The data taken on a single-crystalline sample along the orthorhombic crystal axes reveal a pronounced anisotropy, with the largest length changes along the $b$ axis. The large values of the step sizes $\Delta \alpha$ at the magnetic and superconducting phase transitions provide solid evidence for bulk magnetism and superconductivity. Specific-heat measurements corroborate bulk superconductivity. Thermal-expansion measurements in magnetic fields $B \parallel a,b$ show $\Delta \alpha$ at $T_C$ grows rapidly, which indicates the character of the ferromagnetic transition becomes first-order-like.

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A. Gasparini, Y. K. Huang, J. Hartbaum, H. von Lohneysen, A. de Visser. 2010-08-16. Thermal expansion of the superconducting ferromagnet UCoGe. https://doi.org/10.1103/physrevb.82.052502

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