FeCr2S4 in magnetic fields: possible evidence for a multiferroic ground state

Autor: Manfred Reehuis, Clemens Ulrich, Joachim Deisenhofer, D. V. Quach, J. R. Groza, Stephan Krohns, F. Schrettle, V. Tsurkan, Andrew J Studer, Alois Loidl, Joel Bertinshaw, M. Wohlauer, A. Günther, Maxim Avdeev
Jazyk: angličtina
Rok vydání: 2014
Předmět:
Zdroj: Scientific Reports.
ISSN: 2045-2322
DOI: 10.1038/srep06079
Popis: We report on neutron diffraction, thermal expansion, magnetostriction, dielectric, and specific heat measurements on polycrystalline FeCr2S4 in external magnetic fields. The ferrimagnetic ordering temperatures $T_{\mathrm{C}}\approx 170$ K and the transition at $T_{\mathrm{OO}}\approx 10$ K, which has been associated with orbital ordering, are only weakly shifted in magnetic fields up to 9 T. The cubic lattice parameter is found to decrease when entering the state below $T_{\mathrm{OO}}$. The magnetic moments of the Cr- and Fe-ions are reduced from the spin-only values throughout the magnetically ordered regime, but approach the spin-only values for fields $>$5.5 T. Thermal expansion in magnetic fields and magnetostriction experiments indicate a contraction of the sample below about 60 K. Below $T_{\mathrm{OO}}$ this contraction is followed by a moderate expansion of the sample for fields larger than $\sim$4.5 T. The transition at $T_{\mathrm{OO}}$ is accompanied by an anomaly in the dielectric constant. The dielectric constant depends on both the strength and orientation of the external magnetic field with respect to the applied electric field for $T
Comment: 23 pages, 5 figures
Databáze: OpenAIRE