Multiferroic properties of the buckled staircase Kagome compound Mn3V2O8

In multiferroics at least two ferroic orders coexist and we are interested in systems with the coexistence of magnetic ordering (MO) and electric polarization (EP). A strong coupling between them leads to technical applications such as MERAMs or MESO logics. However, the complex coupling mechanism and the origin of EP are not well understood. In this work we are interested in the multiferroic properties of the buckled Kagome staircase lattice compounds (BKSL) M₃V₂O₈ (M=Co, Ni and Mn). In BKSL, edge-shared magnetic M²⁺ octahedra layers are interconnected by the nonmagnetic V⁵⁺ tetrahedra. The magnetic ions M²⁺ forms a staircase of the buckled M²⁺ layers resulting in two distinct M²⁺ sites. This influences the various exchange couplings which reduces the spin frustration expected from an ideal Kagome lattice, resulting in a rich magnetic phase diagram. Co₃V₂O₈ (CVO) and Ni₃V₂O₈ (NVO), have 5 and 4 magnetic phase transitions respectively. NVO is a prototype compound for MO induced multiferroicity in its cycloidal magnetic phase. Very recently EP was reported in CVO which is induced by a structural distortion, differing from NVO. We are interested in Mn₃V₂O₈, which is less investigated compared to CVO and NVO. We have characterized it’s multiferroic properties by means of neutron scattering, bulk magnetic and dielectric measurements.