Eur. Phys. J. B 45, 197-201 (2005)
https://doi.org/10.1140/epjb/e2005-00054-2

Perpendicular exchange bias and its control by magnetic, stress and electric fields

¹ Department of Physics and Astronomy and the Center for Materials Research and Analysis, 203 Ferguson Hall, University of Nebraska, Lincoln, NE 68588-0111, USA
² Angewandte Physik, Universität Duisburg-Essen, 47048 Duisburg, Germany

Corresponding author: ^a kleemann@uni-duisburg.de

Received: 15 September 2004
Published online: 8 March 2005

Abstract

Perpendicular exchange bias (PEB) involving perpendicular magnetic anisotropy (PMA) in both the antiferromagnetic (AF) pinning and the ferromagnetic (FM) sensor layer is expected to become important in future perpendicular recording and sensing devices. Further, because of the reduced spin dimensionality, PEB promises to be easier understandable than the conventional planar exchange bias (EB). In addition to its first realization using the Ising-type AF compounds FeF₂ and FeCl₂ we have tested control strategies of EB being alternative to the conventional magnetic and thermal ones. Indeed, specific symmetry properties of the pinning layer have been shown to enable mechanical (viz. piezomagnetic via FeF and electric control (viz. magneto-electric via Cr₂O of EB, respectively. Electric control promises to become relevant for TMR devices in MRAM technology.