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Magnetismus Poster: Do., 13:00–15:30 D-P252
Fine-tuning the SDW in Cr/V heterostructures by hydrogen loading
Arndt Remhof 1 , Evgeny Kravtsov 1 , Gregor Nowak 1 , Alexei Nefedov 1 ,
Florin Radu 1 , Andreas Liebig 2 , Björgvin Hjörvarsson 2 , Andreas Hoser 3 ,
Luigi Paolasini 4 , Hartmut Zabel 1
1 Department of Physics, Ruhr-University Bochum, D-44780 Bochum, Germany –
2 Materials Physics, Department of Physics, Uppsala University, Box 530, SE-751 21
Uppsala, Sweden – 3 Institut für Kristallographie, RWTH-Aachen, D-52056 Aachen,
Germany and Institut für Festkörperforschung, Forschungszentrum Jülich, D-52425,
Germany – 4 European Synchrotron Radiation Facility, 6 rue Jules Horowitz, F-38000
Grenoble, France
Spin-density wave (SDW) state in thin Cr films is known to be under influence of
dimensionality (film thickness) and proximity effects from neighboring layers. Here
we report on a combined neutron and X-ray scattering study of these effects of H
loading on a [Cr(500ML)/V(14ML)]×4 superlattice. The neutron measurements have
been performed at the Forschungszentrum Jülich (UNIDAS) while the synchrotron
measurements were carried out at the ESRF (ID20). Exposed to a hydrogen atmosphere
of up to 1 bar, the sample takes up H quickly. As the dissolved H only resides
in the V lattice, it does not influence directly the intrinsic properties of the Cr. It
modifies the SDW state via the boundary conditions in proximity with the H-loaded
V. It was found that H in the V layers favors the commensurate phase, shifting the
commensurate-incommensurate phase coexistence to lower Temperatures. This research
was supported by SFB 491 an by the INTAS project ref. nr. 03-51-4778.
Fig. 1: Neutron scattering
scans taken in the L direction
around the Cr(010) reflection
in the H-loaded state
(pH2=100mbar) to explore
the SDW polarization. Scans
recorded at different temperatures
are depicted with an
offset in the vertical direction
for clarity. The incommensurate
phase can be identified
by the two satellite reflections
at L=±0.04, while the reflection
at L=0 is indicative for
the commensurate phase.