Strain-induced magnetic phase transition in SrCoO3−δ thin films

It has been well established that both in bulk at ambient pressure and for films under modest strains, cubic SrCoO3−δ (δ<0.2) is a ferromagnetic metal. Recent theoretical work, however, indicates that a magnetic phase transition to an antiferromagnetic structure could occur under large strain accompanied by a metal-insulator transition. We have observed a strain-induced ferromagnetic-to-antiferromagnetic phase transition in SrCoO3−δ films grown on DyScO3 substrates, which provide a large tensile epitaxial strain, as compared to ferromagnetic films under lower tensile strain on SrTiO3 substrates. Magnetometry results demonstrate the existence of antiferromagnetic spin correlations and neutron diffraction experiments provide a direct evidence for a G-type antiferromagnetic structure with Neél temperatures between TN∼135±10K and ∼325±10K, depending on the oxygen content of the samples. Therefore, our data experimentally confirm the predicted strain-induced magnetic phase transition to an antiferromagnetic state for SrCoO3−δ thin films under large epitaxial strain. © 2015 American Physical Society.

Keywords

Ferroelectric materials, Strains, Magnetism, Temperature control, Oxygen, Data

Citation

Callori, S. J., Hu, S., Bertinshaw, J., Yue, Z. J., Danilkin, S., Wang, X. L., Nagarajan, V., Klose, F., Seidel, J., Ulrich, C. (2015). Strain-induced magnetic phase transition in SrCoO3-delta thin films. Physical Review B, 91(14), 140405. doi:10.1103/PhysRevB.91.140405