Magnetization study of interlayer exchange in semiconductor EuS-PbS ferromagnetic wedge multilayers
|Leszek Kowalczyk 1, Victor Osinniy 1, Marina Chernyshova 1, Piotr Dziawa 1, Tomasz Story 1, Coen J. Smits 2, Henk J. Swagten 2, Alexander Y. Sipatov 3, Valentin V. Volobuev 3|
1. Polish Academy of Sciences, Institute of Physics, al. Lotników 32/46, Warszawa 02-668, Poland
In EuS-PbS semiconductor multilayers grown epitaxially along  crystal direction on either PbS or KCl substrates the layers of EuS (a model Heisenberg ferromagnet) are antiferromagnetically coupled via diamagnetic PbS spacer layer. For the experimental analysis of this effect neutron diffraction and reflectivity as well as SQUID magnetometry methods were applied to study the spacer thickness and temperature dependence of the coupling mechanism. In this work we present the analysis of the interlayer coupling in EuS-PbS multilayer wedge structures grown on KCl (001) substrates with the wedges covering the PbS spacer layer thickness from 6 to 0.3 nm. The structural parameters of the wedges were examined by the x-ray diffraction analysis of the EuS-PbS superlattice period. We discuss the measurements of magnetic hysteresis loops of EuS-PbS structures performed by both SQUID (for small terminal parts of the wedge) and MOKE (magneto-optical analysis along the wedge) magnetometry. The strong changes of magnetic remanence, coercive field and saturation field are observed for EuS-PbS structures with the PbS spacer thinner than about 1.5 nm. To model the magnetic field and temperature dependence of the magnetization of these structures, the temperature dependent interlayer exchange, in-plane anisotropy and Zeeman energy contributions are considered.
Work supported by KBN research project PBZ-KBN-044/P03/2001.
Presentation: poster at E-MRS Fall Meeting 2005, Symposium D, by Leszek Kowalczyk
See On-line Journal of E-MRS Fall Meeting 2005
Submitted: 2005-06-01 09:50 Revised: 2009-06-07 00:44