Multi-ferroic magnetoelectrics

Abstract

Domain aspects of multi-fe rroics are reviewed, i.e. of materials, in which two or all three of 1he properties ·rerroeleclricily.' •fcrromagnelism' and ·fe rroelasticity' occur simultaneo usly in the same phase, and in which the magnelic poinl group has been reliably established by magneiOelectric, optical, dielectric, magnetic and related studies on single crystals and single domains. Nearly o nly members of lhc boracitc cryslal famil y are concem ed, whereas fo r 1he pcrovskile fami ly and other classes of material there is great pauci1y of data on single crystals. Polarized lighl microscopy is shown to be an indispensable tool for the s1udy of multi-ferroics. in particular when ferroelasticity is involved. Potenlial multi-fcrroic magnetoclectrics. so far only kno wn in ceramic form . are excluded from the survey.

Multiferroics: Different ways to combine magnetism and ferroelectricity

“…Such are for example many borates, containing BO 3 groups, e.g. GdFe 3 (BO 3 ) 4 . These materials display interesting properties, especially optical ones [15], but one should not in general expect very strong coupling between magnetic and electric degrees of freedom here, although some coupling of course should be present.…”

“…The attempts to combine in one system both the (ferro)magnetic and ferroelectric (FE) properties started in 1960's, predominantly by two groups in then the Soviet Union: the group of Smolenskii in St.Petersburg (then Leningrad) [1] and by Venevtsev in Moscow [2]. Materials combining these different "ferroic" [3] properties were later on called "multiferroics" [4]. For some time this field of research was very ``quiet'' and not well known.…”

Defect Chemistry as a Crystal Structure Design Parameter: Intrinsic Point Defects and Ga Substitution in InMnO3

“…The search for multiferroic materials, with their multiple coexisting ferroic orders, has been a hotbed of research activity in recent decades [1][2][3][4][5] and has led to the identification of new mechanisms for ferroelectricity that are compatible with the coexistence of magnetism. 6 The so-called improper geometric ferroelectricity identified in the rare-earth hexagonal manganites, RMnO 3 (R=Sc, Y, Dy, Ho, Er, Tm, Yb, Lu, In), is of particular interest and has stimulated research in topics as diverse as high-temperature multiferroism, 7 nanodevices 8,9 and testing of early-universe theories.…”

Determination of surface and interface magnetic properties for the multiferroic heterostructure Co/BaTiO3using spleed and arpes

“…This special class of materials is named multiferroics and was introduced first in the 1960's by Smolenskii and Venevtsev [1,2]. In 1994 the interest in this topic has been renewed by H. Schmid [3], who introduced first the synomym multiferroics.…”