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arXiv · 1004.4751

Potassium-doped BaFe2As2 superconducting thin films with a transition temperature of 40 K

Nam Hoon Lee·Soon-Gil Jung·Dong Ho Kim·Won Nam Kang
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Abstract

We report the growth of potassium-doped BaFe2As2 thin films, where the major charge carriers are holes, on Al2O3 (0001) and LaAlO3 (001) substrates by using an ex-situ pulsed laser deposition technique. The measured Tc's are 40 and 39 K for the films grown on Al2O3 and LaAlO3, respectively and diamagnetism indicates that the films have good bulk superconducting properties below 36 and 30 K, respectively. The X-ray diffraction patterns for both films indicated a preferred c-axis orientation, regardless of the substrate structures of LaAlO3 and Al2O3. The upper critical field at zero temperature was estimated to be about 155 T.

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Nam Hoon Lee, Soon-Gil Jung, Dong Ho Kim, Won Nam Kang. 2010-04-27. Potassium-doped BaFe2As2 superconducting thin films with a transition temperature of 40 K. https://doi.org/10.1063/1.3431583

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