2018/10/02 by K. E. Siewierska, N. Teichert, R. Schäfer +2 · 8 citations
Materials Science · Physics and Astronomy · #Anisotropy #Antiferromagnetism #Chemical and Physical Properties of Materials #Demagnetizing field #Domain wall (magnetism) #Ferrimagnetism #Ferromagnetism #Hysteresis #Kerr effect #Magnetic domain #Magnetic properties of thin films #Magnetization #Theoretical and Computational Physics #cond-mat.mtrl-sci
paper · pdf · doi:10.1109/tmag.2018.2869016
published in IEEE Transactions on Magnetics 55(2), 1-4 (IEEE Magnetics Society)
openalex publication_date 2018/10/02 · openalex created_date 2018/10/12 · arxiv created 2018/12/13 · arxiv updated 2018/12/14 · openalex updated_date 2026/08/05
We have a choice of methods for examining domains at the surface of a ferromagnet that depend on probing the stray field distribution, but these methods do not work in antiferromagnets or compensated ferrimagnets, which produce no stray field. The discovery of compensated ferrimagnetic half metals allows for the local magnetization state to be observed directly with polarized light. The example considered here, Mn2RuxGa, has two inequivalent but oppositely aligned Mn sublattices with equal and opposite moments, but only one of them contributes spin-polarized conduction electrons at the Fermi energy. The material looks like an antiferromagnet from the outside, but from the point of view of the electronic structure, it resembles a spin-polarized ferromagnetic metal. The anisotropy axis is perpendicular to the film plane, which allows domains to be imaged directly by polar magneto-optic Kerr effect. The domain structure in a film with a composition of Mn2Ru0.4Ga has been imaged in a Kerr microscope and hysteresis loops have been traced. Domains have dimensions of order 20 μm with meandering domain walls and a fractal dimension Df= 1.85. Our results open new direct imaging possibilities of magnetically ordered materials with no net moment.