Origin of the large ferroelectric polarization enhancement under high pressure for multiferroic DyMnO3 studied by polarized and unpolarized neutron diffraction

Using unique experimental setups allowing spherical neutron polarimetry (SNP) and unpolarized neutron diffraction at pressure up to 8 GPa, this collaboration of authors from Japan, France, and the UK investigates pressure- and magnetic field induced gigantic ferroelectricity in multiferroic DyMnO${}_{3}$. This work reveals that the exchange striction for rare-earth and Mn bonds is strongly related to the ferroelectric polarization enhancement in DyMnO${}_{3}$. It also proves the feasibility of the SNP experiment under high pressure, which will encourage researchers to investigate pressure-induced magnetic ordering.