Filters

20162

More filters

20192
Reset filters

Settings

DDC: 620 × Publisher: London : Nature Publishing Group × Subject: Ferromagnetism × Subject: Magnetic properties and materials ×

Search Results

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Robust and tunable itinerant ferromagnetism at the silicon surface of the antiferromagnet GdRh2Si2
    (London : Nature Publishing Group, 2016) Güttler, M.; Generalov, A.; Otrokov, M.M.; Kummer, K.; Kliemt, K.; Fedorov, A.; Chikina, A.; Danzenbächer, S.; Schulz, S.; Chulkov, E.V.; Koroteev, Yu. M.; Caroca-Canales, N.; Shi, M.; Radovic, M.; Geibel, C.; Laubschat, C.; Dudin, P.; Kim, T.K.; Hoesch, M.; Krellner, C.; Vyalikh, D.V.
    Spin-polarized two-dimensional electron states (2DESs) at surfaces and interfaces of magnetically active materials attract immense interest because of the idea of exploiting fermion spins rather than charge in next generation electronics. Applying angle-resolved photoelectron spectroscopy, we show that the silicon surface of GdRh2Si2 bears two distinct 2DESs, one being a Shockley surface state, and the other a Dirac surface resonance. Both are subject to strong exchange interaction with the ordered 4f-moments lying underneath the Si-Rh-Si trilayer. The spin degeneracy of the Shockley state breaks down below ~90 K, and the splitting of the resulting subbands saturates upon cooling at values as high as ~185 meV. The spin splitting of the Dirac state becomes clearly visible around ~60 K, reaching a maximum of ~70 meV. An abrupt increase of surface magnetization at around the same temperature suggests that the Dirac state contributes significantly to the magnetic properties at the Si surface. We also show the possibility to tune the properties of 2DESs by depositing alkali metal atoms. The unique temperature-dependent ferromagnetic properties of the Si-terminated surface in GdRh2Si2 could be exploited when combined with functional adlayers deposited on top for which novel phenomena related to magnetism can be anticipated.
  • Thumbnail Image
    Item
    Rashba torque driven domain wall motion in magnetic helices
    (London : Nature Publishing Group, 2016) Pylypovskyi, Oleksandr V.; Sheka, Denis D.; Kravchuk, Volodymyr P.; Yershov, Kostiantyn V.; Makarov, Denys; Gaididei, Yuri
    Manipulation of the domain wall propagation in magnetic wires is a key practical task for a number of devices including racetrack memory and magnetic logic. Recently, curvilinear effects emerged as an efficient mean to impact substantially the statics and dynamics of magnetic textures. Here, we demonstrate that the curvilinear form of the exchange interaction of a magnetic helix results in an effective anisotropy term and Dzyaloshinskii–Moriya interaction with a complete set of Lifshitz invariants for a one-dimensional system. In contrast to their planar counterparts, the geometrically induced modifications of the static magnetic texture of the domain walls in magnetic helices offer unconventional means to control the wall dynamics relying on spin-orbit Rashba torque. The chiral symmetry breaking due to the Dzyaloshinskii–Moriya interaction leads to the opposite directions of the domain wall motion in left- or right-handed helices. Furthermore, for the magnetic helices, the emergent effective anisotropy term and Dzyaloshinskii–Moriya interaction can be attributed to the clear geometrical parameters like curvature and torsion offering intuitive understanding of the complex curvilinear effects in magnetism.