Giant magnetoelectric effects achieved by tuning spin cone symmetry in Y-type hexaferrites

Abstract

Multiferroics materials, which exhibit coupled magnetic and ferroelectric properties, have attracted tremendous research interest because of their potential in constructing next-generation multifunctional devices. The application of single-phase multiferroics is currently limited by their usually small magnetoelectric effects. Here, we report the realization of giant magnetoelectric effects in a Y-type hexaferrite Ba0.4Sr1.6Mg2Fe12O22 single crystal, which exhibits record-breaking direct and converse magnetoelectric coefficients and a large electric-field-reversed magnetization. We have uncovered the origin of the giant magnetoelectric effects by a systematic study in the Ba2-xSrxMg2Fe12O22 family with magnetization, ferroelectricity and neutron diffraction measurements. With the transverse spin cone symmetry restricted to be two-fold, the one-step sharp magnetization reversal is realized and giant magnetoelectric coefficients are achieved. Our study reveals that tuning magnetic symmetry is an effective route to enhance the magnetoelectric effects also in multiferroic hexaferrites.

Strain-induced robust magnetic anisotropy and room temperature magnetoelectric coupling effect in epitaxial SmFeO3 film

“…In order to explain the origin of the magnetically induced ferroelectricity, a large number of theoretical models were proposed one after another, such as reverse Dzyaloshinskii-Moriya (D-M) interaction [12], spin-dependent p-d hybridization and exchange striction mechanism [13,14]. So far, numerous single-phase multiferroic materials have been found, such as (Y, Sr, Gd, Dy, Tb, Ho, Lu)MnO 3 films [15][16][17][18], (Dy, Gd, Tb, Ho, Er, Lu)CrO 3 films [19][20][21][22][23], (Gd, Dy, Yb)FeO 3 films [24][25][26], EuTiO 3 films [27], hexaferrite Ba 2−x Sr x Mg 2 Fe 12 O 22 single crystal [28], and LaFeO 3 polycrystal [29]. Despite rich characteristics and fascinating physics, the low working temperature and weak saturation magnetization (M s ) restrict the practical applications of these materials.…”

Large linear magnetoelectric effect and field-induced ferromagnetism and ferroelectricity in DyCrO4

“…The TbPO 4 single crystal is an extraordinary example with an α value up to 730 ps m −1 but only below a lower AFM transition temperature of 2.38 K 7 . It is worth noting that a few ME multiferroics exhibit very large ME effects 19,[37][38][39][40][41] . However, they often only occur near the phase transition boundaries, while away from them, the ME effects are considerably reduced.…”

DEMAND, a Dimensional Extreme Magnetic Neutron Diffractometer at the High Flux Isotope Reactor

“…So far, the high-pressure experiments are only used for qualitative studies because neutron absorption caused by the gasket and the pressure medium varies with pressure. It requires more High pressure studies have been performed on a Ba 0.4 Sr 1.6 Mg 2 Fe 12 O 22 hexaferrite crystal that presents a new magnetoelectric coefficient record for single-phase materials [15] by using Diamond Anvil Cells (DACs) that were designed at ORNL [16,17]. Both polycrystalline diamond (Versimax ® ) and single-crystal diamond anvil cells have been used.…”