9 research outputs found
Phenomenological Landau analysis of predicted magnetoelectric fluorides: KMnFeF and BaNiF
Recently, we predicted based on symmetry considerations that KMnFeF and
BaNiF are likely magnetoelectric multiferroic materials. In
this contribution, we investigate with Landau theory and crystal structure
considerations the polarization and the linear magnetoelectric effect in these
materials. Based on these two examples, we show that any magnetoferroelectric
will display additional electrical polarization below its magnetic ordering
temperature. This additional electrical polarization is not related to the
linear magnetoelectric effect. Its magnitude depends on the dielectric
susceptibility.Comment: 11 pages, accepted for publication in Journal of Physics: Condensed
Matte
Prediction for new magnetoelectric fluorides
We use symmetry considerations in order to predict new magnetoelectric
fluorides. In addition to these magnetoelectric properties, we discuss among
these fluorides the ones susceptible to present multiferroic properties. We
emphasize that several materials present ferromagnetic properties. This
ferromagnetism should enhance the interplay between magnetic and dielectric
properties in these materials.Comment: 12 pages, 4 figures, To appear in Journal of Physics: Condensed
Matte
Experimental evidence for an intermediate phase in the multiferroic YMnO3
We have studied YMnO by high-temperature synchrotron X-ray powder
diffraction, and have carried out differential thermal analysis and dilatometry
on a single crystal sample. These experiments show two phase transitions at
about 1100K and 1350K, respectively. This demonstrates the existence of an
intermediate phase between the room temperature ferroelectric and the high
temperature centrosymmetric phase. This study identifies for the first time the
different high-temperature phase transitions in YMnO.Comment: 10 pages 5 figures. New version, Additional data, Journal of Physics:
Condensed Matter, in Pres
Magnetodielectric coupling by exchange striction in Y 2Cu 2O 5
77.22.-d Dielectric properties of solids and liquids, 75.80.+q Magnetomechanical and magnetoelectric effects, magnetostriction, 77.80.-e Ferroelectricity and antiferroelectricity, 75.30.Kz Magnetic phase boundaries,