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arXiv · 1003.4907

Low temperature specific heat in BaFe1.9Ni0.1As2 single crystals

Bin Zeng·Gang Mu·Huiqian Luo·Hai-Hu Wen
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Abstract

Low-temperature specific heat was measured on the BaFe1.9Ni0.1As2 single crystals with critical transi-tion temperature Tc = 20.1 K. A clear specific heat jump with the value \DeltaC/T|Tc \approx 23 mJ/mol K^2 has been observed. In addition, a roughly linear magnetic field dependence of the electronic specific heat coefficient \Delta\gamma(H) is found in the zero-temperature limit, suggesting that at least one Fermi pocket, probably the hole derivative one, is fully gapped with a small anisotropy in the present sample. A slight curvature of the curve \Delta\gamma(H) may suggest a complex gap structure (anisotropic gap or nodes) at other Fermi surfaces.

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Bin Zeng, Gang Mu, Huiqian Luo, Hai-Hu Wen. 2010-03-25. Low temperature specific heat in BaFe1.9Ni0.1As2 single crystals. https://arxiv.org/abs/1003.4907

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