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arXiv · 1907.04031

Multiple gaps revealed by low temperature specific heat in the 1111-type CaFe_{0.88}Co_{0.12}AsF single crystals

Jianan Chu·Teng Wang·Yonghui Ma·Jiaxin Feng·Lingling Wang·Xuguang Xu·Wei Li·Gang Mu·Xiaoming Xie
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Abstract

Low-temperature specific heat (SH) is measured on the 1111-type CaFe_{0.88}Co_{0.12}AsF single crystals under different magnetic fields. A clear SH jump with the height \Delta C/T|_Tc = 10.4 mJ/mol K^2 was observed at the superconducting transition temperature T_c. The electronic SH coefficient \Delta\gamma (B) increases linearly with the field below 5 T and a kink is observed around 5 T, indicating a multi-gap feature in the present system. Such a sign is also reflected in the Tc-B data. A detailed analysis shows that this behavior can be interpreted in terms of a two-gap scenario with the ratio \Delta_L=\Delta_S = 2:8-4:5.

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Jianan Chu, Teng Wang, Yonghui Ma, Jiaxin Feng, Lingling Wang, Xuguang Xu, Wei Li, Gang Mu, Xiaoming Xie. 2019-07-09. Multiple gaps revealed by low temperature specific heat in the 1111-type CaFe_{0.88}Co_{0.12}AsF single crystals. https://doi.org/10.1088/1361-648x/ab34b8

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