Floating zone growth of large single crystals of SrFeO3−δ

The Fe4+-containing cubic perovskite phase SrFeO3−δ is of interest both for its high-temperature, oxygen-conducting properties as a solid oxide fuel cell component, and at low temperatures, where it exhibits a plethora of helical magnetic phases and a candidate Skyrmion lattice. However, a sequence of structural phase transitions encountered on cooling to room temperature has limited the size of single crystals. We report the floating-zone growth and oxygen-annealing of multiple-cubic-centimetre-sized single crystals of SrFeO3−δ, suitable for inelastic neutron scattering and other measurement techniques requiring large sample volumes. ► Single crystals of SrFeO3 were grown by the floating zone technique. ► The addition of a shield to quench the crystal prevented shattering. ► An annealing technique is described. ► The crystals were characterized. ► Transport and magnetic measurements are reported.