Campus Units
Physics and Astronomy, Ames Laboratory
Document Type
Article
Publication Version
Accepted Manuscript
Publication Date
8-3-2011
Journal or Book Title
JETP Letters
Volume
93
First Page
667
DOI
10.1134/S0021364011110038
Abstract
We report measurements of the temperature dependence of the radio frequency magnetic penetration depth in Ba0.68K0.32Fe2As2 and Ba(Fe0.93Co0.07)2As2 single crystals in pulsed magnetic fields up to 60 T. From our data, we construct an H-T-phase diagram for the inter-plane (H ‖ c) and in-plane (H ‖ ab) directions for both compounds. For both field orientations in Ba0.68K0.32Fe2As2 we find a concave curvature of the H c2(T) lines with decreasing anisotropy and saturation towards lower temperature. Taking into account Pauli spin paramagnetism we can describe H c2(T) and its anisotropy. In contrast, we find that Pauli paramagnetic pair breaking is not essential for Ba(Fe0.93Co0.07)2As2. For this electron-doped compound, the data support a H c2(T) dependence that can be described by the Werthamer-Helfand-Hohenberg model for H ‖ ab and a two-gap behavior for H ‖ c.
Copyright Owner
Springer Nature
Copyright Date
2011
Language
en
File Format
application/pdf
Recommended Citation
Gasparov, V. A.; Drigo, L.; Audouard, A.; Sun, D. L.; Lin, C. T.; Bud’ko, Sergey L.; Canfield, Paul C.; Wolff-Fabris, F.; and Wosnitza, J., "Upper critical magnetic field in Ba0.68K0.32Fe2As2 and Ba(Fe0.93Co0.07)(2)As-2" (2011). Physics and Astronomy Publications. 656.
https://lib.dr.iastate.edu/physastro_pubs/656
Comments
This is a post-peer-review, pre-copyedit version of an article published in JETP Letters. The final authenticated version is available online at DOI: 10.1134/S0021364011110038. Posted with permission.