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arXiv · 1004.5557

Coherent interfacial bonding on the FeAs tetrahedron in Fe/Ba(Fe(1-x)Co(x))2As2 bilayers

Thomas Thersleff·Kazumasa Iida·Silvia Haindl·Martin Kidszun·Darius Pohl·Andreas Hartmann·Fritz Kurth·Jens Haenisch·Ruben Huehne·Bernd Rellinghaus·Ludwig Schultz·Bernhard Holzapfel
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Abstract

We demonstrate the growth of epitaxial Fe/Ba(Fe(1-x)Co(x))2As2 (Fe/Ba-122) bilayers on MgO(001) and LSAT(001) single crystal substrates using Pulsed Laser Deposition (PLD). By exploiting the metallic nature of the FeAs tetrahedron in the Ba-122 crystal structure, we achieve a coherent interfacial bond between bcc iron and Co-doped Ba-122. Tc values for both bilayers were close to that of the PLD target. Direct observation of interfacial bonding between Fe and the Ba-122 FeAs sublattice by atomic resolution transmission electron microscopy implies that this bilayer architecture may work for other iron pnictide systems and pave the way for the fabrication of superconducting/ferromagnetic heterostructures.

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Thomas Thersleff, Kazumasa Iida, Silvia Haindl, Martin Kidszun, Darius Pohl, Andreas Hartmann, Fritz Kurth, Jens Haenisch, Ruben Huehne, Bernd Rellinghaus, Ludwig Schultz, Bernhard Holzapfel. 2010-04-30. Coherent interfacial bonding on the FeAs tetrahedron in Fe/Ba(Fe(1-x)Co(x))2As2 bilayers. https://doi.org/10.1063/1.3457432

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