Abstract

We have found that SmFeO3, a family of rare-earth orthoferrites, exhibits temperature-induced magnetization reversal below the critical low-temperature along the a-axis of Pbnm symmetry. First-principles calculations demonstrate that this negative magnetization is mainly attributed to the competition between two magnetocrystalline anisotropy terms in the inequivalent magnetic sites of Sm3+ and Fe3+. Interestingly, the room temperature magnetization-field curve further shows an ultra-fast magnetization switch in the low-magnetic field, suggesting a potential applicability to high-speed magnetic switching devices.