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Magnetismus Poster: Do., 13:00–15:30 D-P234
Increased Curie-temperature in an osmate double perovskite by 5d-doping
Yoshiharu Krockenberger 1,2 , Kaylash Mogare 2 , Manfred Reehuis 2,3 , Martin
Tovar 3 , Andreas Winkler 1 , Martin Jansen 2 , Lambert Alff 1
1 Darmstadt University of Technology, Petersenstr. 23, 64287 Darmstadt, Germany
– 2 Max-Planck-Institute for Solid State Research, Heisenbergstr. 1, 70569 Stuttgart,
Germany – 3 Hahn-Meitner-Institut (HMI), 10634 Berlin, Germany
Within the group of ferrimagnetic double perovskites of the type A2MNO6 (with A
an alkaline earth, M a magnetic transition metal ion, and N a non-magnetic ion),
a huge spread of magnetic transition temperatures is observed. We show for the example
of the Cr-based double perovskites that increased band-filling by introducing
elements with an increased number of 5d electrons leads to a strongly enhanced Curietemperature.
Along this line the slightly rhombohedral compound Sr2CrOsO6 has a
Curie-temperature of about 750 K. The magnetic structure determined by neutron
scattering and x-ray magnetic circular dichroism (XMCD) experiments confirms the
existence of a sizable induced magnetic moment at the Os-site. This result is consistent
with the picture that to a large extent spin-polarized electrons mediate a robust
ferrimagnetic order in Sr2CrOsO6.