Chemical Substitution‐Induced Ferroelectric Polarization Rotation in BiFeO3

Chemical substitution-induced continuous ferroelectric polarization rotation in BiFeO3 is discovered. Rare-earth-substituted BiFeO3 is a unique system in which the ferroelectric polarization vector continuously rotates, and by controlling the composition via substitution, a particular direction of the polarization vector may be ‘dialled up’ with an arbitrary angle between the [111] and [001] directions.