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arXiv · 0903.4950

Magnetic and dielectric properties in the langasite-type compounds : A3BFe3D2O14 with A=Ba, Sr, Ca, B=Ta, Nb, Sb and D=Ge, Si

Karol Marty·Pierre Bordet·Virginie Simonet·Mickael Loire·Rafik Ballou·Céline Darie·Jakob Kljun·Pierre Bonville·Olivier Isnard·Pascal Lejay·Bartosz Zawilski·Charles Simon
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Abstract

The Fe-based langasites are the first reported compounds presenting a magnetic ordering in this rich family, besides being well known for piezo-electric properties and optical activity. The structural, magnetic and dielectric properties of the Fe langasite compounds, with various substitution of non-magnetic cations, have been studied with x-ray and neutron diffraction, magnetostatic measurements, M\"ossbauer spectroscopy, and dielectric measurements. The title compounds (trigonal, space group P321) display a helical magnetic order with signatures of frustration below TN ~24- 35 K where an anomaly of the dielectric permittivity is observed. The influence of the cationic substitutions and the nature of the magnetoelectric coupling is hereafter addressed.

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Karol Marty, Pierre Bordet, Virginie Simonet, Mickael Loire, Rafik Ballou, Céline Darie, Jakob Kljun, Pierre Bonville, Olivier Isnard, Pascal Lejay, Bartosz Zawilski, Charles Simon. 2009-03-28. Magnetic and dielectric properties in the langasite-type compounds : A3BFe3D2O14 with A=Ba, Sr, Ca, B=Ta, Nb, Sb and D=Ge, Si. https://doi.org/10.1103/physrevb.81.054416

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