Pseudo exchange bias due to rotational anisotropy

Author Ehrmann A.; Komraus S.; Blachowicz T.; Domino K.; Nees M.; Jakobs P.; Leiste H.; Mathes M.; Schaarschmidt M.
Title Pseudo exchange bias due to rotational anisotropy
Journal Journal of Magnetism and Magnetic Materials
Year 2016
Status Published
Volume 412
Pages 7–10
DOI 10.1016/j.jmmm.2016.03.071
Abstract Ferromagnetic nanostructure arrays with particle dimensions between 160 nm and 400 nm were created by electron-beam lithography. The permalloy structures consist of rectangular-shaped walls around a square open space. While measuring their magnetic properties using the Magneto-Optical Kerr Effect (MOKE), in some angular regions an exchange bias (EB) seemed to appear. This paper gives an overview of possible reasons for this “pseudo exchange bias” and shows experimentally and by means of micromagnetic simulations that this effect can be attributed to unintentionally measuring minor loops.