Scanning tunneling microscopy observations of single-crystal Fe∕ MgO∕ Fe magnetic tunnel junctions

Department of Materials Engineering Science, Graduate School of Engineering Science, Core Research for Evolutional Science and Technology (CREST), Osaka University, 560-8531, Toyonaka, Osaka, Japan
Journal of Applied Physics (Impact Factor: 2.18). 04/2006; 99(8). DOI: 10.1063/1.2170069


Scanning tunneling microscopy observations of a single-crystal Fe001 / MgO001 /Fe001 magnetic tunnel junction which shows a large tunnel magnetoresistance effect were performed. Step-and-terrace structures of an epitaxial MgO barrier layer, which are very similar to surfaces of a bottom Fe underlayer, were observed. This indicates that the MgO terraces were grown flatly on each terrace of the Fe electrode. It is supposed that these atomically flat terraces enable a coherent tunneling of electrons through magnetic tunnel junctions. © 2006 American Institute of Physics.

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Available from: Taro Nagahama, Apr 01, 2015
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    • "In particular we apply the theoretical calculations to the case where A and B correspond alternatively to Fe and Co elements. The Fe/Cr/MgO/Fe nanojunction in the (001) plane and similar architectures are interesting candidates for the development of efficient magnetic tunnel junctions, see works of Matsumoto et al. (2009) and Mizuguchi et al. (2006). It is observed that the efficiency of these components is enhanced when an ultra thin layer of Cr is inserted at the interface of an epitaxial nanojunction Fe/MgO/Fe. "
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