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arXiv · 1101.3150

Upper critical field of the 122-type iron pnictide superconductors

L. Jiao·J. L. Zhang·F. F. Balakirev·G. F. Chen·J. L. Luo·N. L. Wang·H. Q. Yuan
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Abstract

The upper critical fields ($H_{c2}$) of the single crystals $\rm(Sr,Na)Fe_2As_2$ and $\rm Ba_{0.55}K_{0.45}Fe_2As_2$ were determined by means of measuring the electrical resistivity, $ \rho_{xx}(\mu_0H)$, using the facilities of pulsed magnetic field at Los Alamos. In general, these compounds possess a very large upper critical field ($H_{c2}(0)$) with a weak anisotropic effect. The detailed curvature of $H_{c2}(T_c)$ may depend on the magnetic field orientation and the sample compositions. We argue that such a difference mainly results from the multi-band effect, which might be modified via doping.

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L. Jiao, J. L. Zhang, F. F. Balakirev, G. F. Chen, J. L. Luo, N. L. Wang, H. Q. Yuan. 2011-01-17. Upper critical field of the 122-type iron pnictide superconductors. https://doi.org/10.1016/j.jpcs.2010.10.070

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