Exceptionally robust magnetism and structure of SrFeO2 above 100 GPa

We report the exceptional structural and magnetic stability of SrFeO2 under pressure by X-Ray Magnetic Circular Dichroism (XMCD) and X-ray Diffraction (XRD) up to the Mbar range. The XMCD data confirms the onset of ferromagnetism above 30 GPa and its stability up to 102 GPa while XRD shows that SrFeO2 structure remains unchanged from 30 GPa up to 111 GPa without any sign of structural transition. Our results demonstrate the robustness of Fe properties under extreme conditions in the square planar environment.