Introduction The investigation of static and dynamic properties of magnetization distribution heterogeneities (0°- domain walls (DWs)) which appear at the local deviations of magnetic anisotropy (defects) is of considerable interest for memory storage applications. Electric field induced switching of magnetic heterogeneity can be produced by the inhomogeneous magnetoelectric (ME) effect [1]. It has been shown that ME effect is strongly connected with magnetic symmetry of the multiferroic [2]. Building of complete symmetry classification of 1D magnetic heterogeneities and qualitative description of induced ferroelectricity in their volume is the aim of this report. M M A A G G N N E E T T I I C C S S Y Y M M M M E E T T R R Y Y O O F F D D E E F F E E C C T T I I N N M M U U L L T T I I F F E E R R R R O O I I C C M M A A T T E E R R I I A A L L Tanygin B.M. Taras Shevchenko Kiev National University, Radiophysics Faculty, Glushkova 2, Kyiv, Ukraine, MSP 01601. E-mail: b.m.tanygin@gmail.com References [1] V.G. Bar'yakhtar, V.A. L'vov, D.A. Yablonskiy, “Inhomogeneous magnetoelectric effect”, JETP Lett. 37, 12 (1983) 673-675. [2] V.G. Bar'yakhtar, et. al: A. M. Prokhorov, A. S. Prokhorov (Eds.), Problems in sol.-state phys., Chapter 2, Mir Publish., Moscow, 1984, pp. 56-80. [3] M. Hehn, D. Lacour, F. Montaigne, J. Briones, “360 degree domain wall generation…”, arXiv:0711.3571v1 [cond-mat.mtrl-sci]. [4] R. Vakhitov and A. Yumaguzin, “Processes of the inhomogeneous magnetization reversal…”, Phys. Met. Metallogr. 106, 5 (2008) 460-464. [5] B. M. Tanygin, O. V. Tychko, “Magnetic symmetry of the plain domain walls…”, Physica B: Condensed Matter 404, 21, 4018-4022 (2009). [6] L. D. Barron, in „Chirality in Natural and Applied Science‟, Eds. W. J. Lough, I. W. Wainer, Oxford, Blackwell Publishing, 2002, p. 53 - 86. Localized spin cycloid: example of magnetization distribution heterogeneity on defect [3] Y Z M(0SA)P(0SA), where “S” is the even and “A” is the odd function Spin helicoid on defect [4] M(SS0)P(00A) Symmetry analysis describes short- and long-range ME interactions: as well as Maxwell's equations and demagnetization/depolarization energy density volumetric distribution. Note, that in scope of analysis of ME properties of material it is usefully to include electrostritive and magnetostrictive energy terms into because they provide connection between electric and magnetic subsystem of crystal via deformation tensor spatial distribution. According to the Neumann’s principle, must be invariant of the crystal crystallographic class (point symmetry of multiferroic paraphase). In case of the thin or multilayered films and other cases of strong surface influence, exception is the last part with symmetry: where is the symmetry class of the sample shape of material because surface bounds the non-local interactions. For example, thin (001) film of cubic m3m1’ crystal has symmetry 4/mmm1’. Terms which must have the identical symmetry in the given crystal (if not then corresponding term is zero) I II Symmetry Class is a magnetic point group of 0°-DW. There are 42 magnetic point groups of 0°-DW [5]. 0°-DWs with the time-invariant chirality [6] Class A S 0 0 0 A A,S A,S 0 0 0 A,S A S S S A A A S A A S A … A,S … A,S … A,S … A,S … A,S … A,S … 0°-DWs with the time-noninvariant chirality 0 S A 0 S A S S 0 0 0 A 0 0 A 0 0 A 0 0 A,S 0 0 A,S … … … … … … … 0°-DWs without the chirality A 0 0 0 0 A A,S 0 0 0 0 A,S A 0 S S 0 A A A S S S A 0 0 S 0 0 A S S S A A A … … … … … … … P P P P Please, cite original work as: B.M. Tanygin, Magnetic Symmetry of Defect in Multiferroic Material, Abstracts of the 11th Europhysical Conference on Defects in Insulating Materials - EURODIM 2010, PECS, Hungary, 2010, B44.