From spin induced ferroelectricity to dipolar glasses: Spinel chromites and mixed delafossites

Journal Article · Thu Nov 15 04:00:00 EST 2012 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/J.JSSC.2012.01.063· OSTI ID:22149883

Martin, C.; Singh, K.; Simon, Ch.; Lebedev, O. I. ^[1]; Turner, S. ^[2]

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1. Laboratoire CRISMAT, UMR 6508 CNRS/ENSICAEN, 6 bd du Marechal Juin, F-14050 CAEN Cedex 4 (France)
2. EMAT, University of Antwerp, B-2020 Antwerp (Belgium)

Magnetoelectric multiferroics showing coupling between polarization and magnetic order are attracting much attention. For instance, they could be used in memory devices. Metal-transition oxides are provided several examples of inorganic magnetoelectric multiferroics. In the present short review, spinel and delafossite chromites are described. For the former, an electric polarization is evidenced in the ferrimagnetic state for ACr{sub 2}O{sub 4} polycrystalline samples (A=Ni, Fe, Co). The presence of a Jahn-Teller cation such as Ni{sup 2+} at the A site is shown to yield larger polarization values. In the delafossites, substitution by V{sup 3+} at the Cr or Fe site in CuCrO{sub 2} (CuFeO{sub 2}) suppresses the complex antiferromagnetic structure at the benefit of a spin glass state. The presence of cation disorder, probed by transmission electron microscopy, favors relaxor-like ferroelectricity. The results on the ferroelectricity of ferrimagnets and insulating spin glasses demonstrate that, in this research field, transition-metal oxides are worth to be studied. - Graphical abstract: Electric polarization as a function of temperature is measured up to T{sub C} in three chromite ferrimagnetic spinels. Largest values are reached for spinels with Jahn-Teller cations at the A site (Ni or Fe). Highlights: Black-Right-Pointing-Pointer Electric polarization is evidenced in the ferrimagnetic state of the chromite spinels. Black-Right-Pointing-Pointer Jahn-Teller cations at the A site of these spinels lead to larger polarization values. Black-Right-Pointing-Pointer Vanadium substituted at the Cr (or Fe) site of delafossites changes the antiferromagnetic state to spin glass. Black-Right-Pointing-Pointer Electric polarization is not the result of magnetic ordering but magnetic disordering in Cr or Fe delafossites. Black-Right-Pointing-Pointer Relaxor-type ferroelectricity or spin induced ferroelectricity can be observed in the delafossites.

• OSTI ID: 22149883
• Journal Information: Journal of Solid State Chemistry, Journal Name: Journal of Solid State Chemistry Vol. 195; ISSN 0022-4596; ISSN JSSCBI
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
ANTIFERROMAGNETISM
CATIONS
CHROMITES
ELECTRICAL PROPERTIES
GLASS
JAHN-TELLER EFFECT
MAGNETIC PROPERTIES
MEMORY DEVICES
NICKEL IONS
OXIDES
POLARIZATION
POLYCRYSTALS
SPIN GLASS STATE
SPINELS
TEMPERATURE DEPENDENCE
TRANSMISSION ELECTRON MICROSCOPY
VANADIUM
VANADIUM IONS