Coexistence of Magnetoelectric and Antiferroelectric-like Orders in Mn₃Ta₂O₈

Abstract

In materials showing a linear magnetoelectric (ME) effect, unconventional functionalities can be anticipated such as electric control of magnetism and nonreciprocal optical responses. Thus, the search for new linear ME materials is of interest in materials science. Here, using a recently proposed design principle of linear ME materials, which is based on the combination of local structural asymmetry and collinear antiferromagnetism, we demonstrate that an anion-deficient fluorite derivative, Mn 3 Ta 2 O 8 , is a new linear ME material. This is evidenced by the onset of magnetic-fieldinduced electric polarization in its collinear antiferromagnetic phase below T N = 24 K. Furthermore, we also find an antiferroelectric-like phase transition at T S = 55 K, which is attributable to an off-center displacement of magnetic Mn 2+ ions. The present study shows that Mn 3 Ta 2 O 8 is a rare material that exhibits both ME and antiferroelectric-like transitions. Thus, Mn 3 Ta 2 O 8 may provide an opportunity to investigate the physics associated with complicated interactions between magnetic (spin) and electric dipole degrees of freedom.

Probing magnetoelectric effect in the spin-modulated magnet Fe2GeO4

“…Here, it should be mentioned that the four remaining components α xy , α xz , α yx , and α zx , are all indeed nonzero despite their small values. The uncertainties and leakage effects are safely excluded in the process of the measurements, as discussed in the paragraphs below [39]. It is reasonable to consider that an obvious distortion will rise in the cycloid spin structure when an external magnetic field is applied along the [1-10] direction below T N1 .…”