%0 Journal Article
%A Angst, Manuel
%A Adiga, Shilpa
%A Gorfman, Semen
%A Ziolkowski, Michael
%A Strempfer, Jörg
%A Grams, Christoph
%A Pietsch, Manuel
%A Hemberger, Joachim
%T Intrinsic Ferroelectricity in Charge-Ordered Magnetite
%J Crystals
%V 9
%N 11
%@ 2073-4352
%C Basel
%I MDPI
%M FZJ-2019-05206
%P 546
%D 2019
%X Single crystalline magnetite Fe 3 O 4 was investigated at low temperatures in the charge ordered state by electric measurements and time-resolved diffraction with voltage applied in-situ. Dielectric spectroscopy indicates relaxor ferroelectric characteristics, with polarization switching observably only at sufficiently low temperatures and in a suitably chosen time-window. PUND measurements with a ms time scale indicate a switchable polarization of about 0.6μC/cm2 . Significant switching occurs only above a threshold field of about 3kV/mm , and it occurs with a time delay of about 20μs . The time-resolved diffraction experiment yields, for sufficiently high voltage pulses, a systematic variation by about 0.1 % of the intensity of the ( 2,2¯,10¯¯¯¯ ) Bragg reflection, which is attributed to structural switching of domains of the non-centrosymmetric Cc structure to its inversion twins, providing proof of intrinsic ferroelectricity in charge ordered magnetite.
%F PUB:(DE-HGF)16
%9 Journal Article
%U <Go to ISI:>//WOS:000502270800001
%R 10.3390/cryst9110546
%U https://juser.fz-juelich.de/record/865929