IMF2017

Room temperature multiferroics have long been a goal of the condensed matter community. A material which exhibits coupled (anti)ferroelectricity and (anti)ferromagnetism with reasonably high ordering temperatures would have imminently practical and widely spanning technological applications. However, to date very few such materials have been discovered ostensibly due to the normally adversarial conditions needed to stabilize either polarization or magnetism. BiFeO₃, with T_C ~ 1100 K, T_N ~ 650 K and polarization P ~ 80 μC/cm­­², has proven the most promising of these materials and so provides a natural starting point in the search for new compounds. Here we report the results of neutron diffraction studies on the related BiCoO₃ material which exhibits a promisingly high T_N of ~ 470 K and has been predicted from DFT calculations to exhibit a large spin-driven ferroelectric polarization of ~160 μC/cm­­². We comment on the coupling between the stabilization of long range magnetic order and the deformation of the CoO₆ octahedra.