Berlin 2018 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

MA: Fachverband Magnetismus

MA 9: Magnetic domain walls

MA 9.1: Vortrag

Montag, 12. März 2018, 15:00–15:15, EB 202

Emergence of antiferromagnetic domains out of domain walls — •Ehsan Hassanpour Yesaghi¹, Mads C. Weber¹, Amadé Bortis¹, Thomas Lottermoser¹, Yusuke Tokunaga², Yasujiro Taguchi³, Yoshinori Tokura³, and Manfred Fiebig¹ — ¹ETH Zurich, Switzerland — ²Univ. of Tokyo, Japan — ³RIKEN CEMS, Japan

Antiferromagnetic (AFM) materials are gaining increasing attention for their potential in technological applications such as spintronics. Strong coupling and faster dynamics as well as robustness against magnetic stray fields are their attractive properties. This robustness, however, makes it chronically difficult to influence AFM states. We propose to manipulate the AFM ordering through the controlled emergence of bulk domains at the phase transition. To demonstrate this, we investigate the weakly-ferromagnetic (wFM) to AFM phase transition in (Dy,Tb)FeO₃ which is driven by strongly coupled ordering of magnetic rare-earth and iron ions. The wFM ordering, which can be influenced by an external magnetic field, can persist as a metastable state in the AFM phase. By employing spatially-resolved magneto-optical methods, we demonstrate that AFM domains can emerge out of antiphase domain boundaries of the metastable wFM phase. Furthermore, we design domain-wall configurations that allow the nucleation of two oppositely oriented AFM domains separated by a wFM domain wall. We show with a simple model that symmetry of the domain wall in one phase is the key to seed the nucleation of the desired domain orientation of the other phase.