X-ray magnetic linear dichroism study of field-manipulated canted antiferromagnetism in epitaxial α−Fe2O3 films

This paper describes manipulation of the antiferromagnetic (AFM) moment by external magnetic field in thin epitaxial nanofilms of $\ensuremath{\alpha}\text{\ensuremath{-}}{\mathrm{Fe}}_{2}{\mathrm{O}}_{3}$---the iron oxide polymorph known for its canted antiferromagnetism above the Morin temperature. The field-driven rotation of the AFM moment has been detected in thin $\ensuremath{\alpha}\text{\ensuremath{-}}{\mathrm{Fe}}_{2}{\mathrm{O}}_{3}$/GaN layers by monitoring the azimuthal field dependence of the x-ray magnetic linear dichroism line shape at ${L}_{23}$ absorption edge of iron. The presence of the tiny canted ferrimagnetic (FM) moment in $\ensuremath{\alpha}\text{\ensuremath{-}}{\mathrm{Fe}}_{2}{\mathrm{O}}_{3}$ makes it possible to manipulate the related AFM moment by applying external magnetic field, monitoring the field-driven rotation of both AFM and FM moments that otherwise can be hardly detected in a nanoscale film by conventional magnetometry. A controllable manipulation of the AFM moment in a thin film by external magnetic field is supposed to be an important keystone for development of the emerging field of AFM spintronics.