We report an unexplored type-II multiferroic order in NiMn O , exhibiting strong linear magnetoelectric coupling above liquid-nitrogen (LN) temperature. The compound becomes ferroelectric at K, coinciding with ferrimagnetic ordering, with a polarization value of C/m for a poling field of 5 kV/cm. At LN temperature, the polarization value increases linearly ( %) with a magnetic field up to 30 kOe. Rietveld refinement of neutron diffraction patterns reveals a ferrimagnetic model with antiparallel moments at tetrahedral and octahedral sites, as well as a canting of octahedral moment persisting up to K. Low-temperature synchrotron diffraction confirms a step-like oxygen displacement during multiferroic ordering, suggesting that the Dzyaloshinskii–Moriya interaction polarizes the intervening oxygen atoms through magnetostriction, providing a microscopic mechanism for spontaneous electric polarization in this linear magnetoelectric multiferroic compound.
Linear magnetoelectric coupling and type-II multiferroic order in NiMn2O4
A. Chatterjee, A. Kumar, P. K. Manna, S. Bedanta, A. Sarma, S. Majumdar, S. M. Yusuf, S. Giri; Linear magnetoelectric coupling and type-II multiferroic order in NiMn2O4. J. Appl. Phys. 14 September 2023; 134 (10): 104103. https://doi.org/10.1063/5.0149744
Download citation file: