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arXiv · 1512.05901

Room temperature exchange bias in BiFeO3 / Co-Fe bilayers

Christian Sterwerf·Markus Meinert·Elke Arenholz·Jan-Michael Schmalhorst·Günter Reiss
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Abstract

Thin highly epitaxial BiFeO$_3$ films were prepared on SrTiO$_3$ (100) substrates by reactive magnetron co-sputtering. Detailed MOKE measurements on BiFeO$_3$/Co-Fe bilayers were performed to investigate the exchange bias as a function of the films thicknesses and Co-Fe stoichiometries. We found a maximum exchange bias of H$_{\mathrm{eb}}$=92 Oe and a coercive field of H$_{\mathrm{c}}$=89 Oe for a 12.5 nm thick BiFeO$_3$ film with a 2 nm thick Co layer. The unidirectional anisotropy is clearly visible in in-plane rotational MOKE measurements. AMR measurements reveal a strongly increasing coercivity with decreasing temperature, but no significant change in the exchange bias field.

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Christian Sterwerf, Markus Meinert, Elke Arenholz, Jan-Michael Schmalhorst, Günter Reiss. 2015-12-26. Room temperature exchange bias in BiFeO3 / Co-Fe bilayers. https://doi.org/10.1109/tmag.2015.2510544

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