0000000000385610
AUTHOR
Jan Zemen
Relativistic Neel-order fields induced by electrical current in antiferromagnets
We predict that a lateral electrical current in antiferromagnets can induce non-equilibrium N\'eel order fields, i.e. fields whose sign alternates between the spin sublattices, which can trigger ultra-fast spin-axis reorientation. Based on microscopic transport theory calculations we identify staggered current-induced fields analogous to the intra-band and to the intrinsic inter-band spin-orbit fields previously reported in ferromagnets with a broken inversion-symmetry crystal. To illustrate their rich physics and utility, we considered bulk Mn2Au with the two spin sublattices forming inversion partners, and a 2D square-lattice antiferromagnet with broken structural inversion symmetry model…
Large Tunneling Anisotropic Magneto-Seebeck Effect in a CoPt|MgO|Pt Tunnel Junction
We theoretically investigate the Tunneling Anisotropic Magneto-Seebeck effect in a realistically-modeled CoPt|MgO|Pt tunnel junction using coherent transport calculations. For comparison we study the tunneling magneto-Seebeck effect in CoPt|MgO|CoPt as well. We find that the magneto-Seebeck ratio of CoPt|MgO|Pt exceeds that of CoPt|MgO|CoPt for small barrier thicknesses, reaching 175% at room temperature. This result provides a sharp contrast to the magnetoresistance, which behaves oppositely for all barrier thicknesses and differs by one order of magnitude between devices. Here the magnetoresistance results from differences in transmission brought upon by changing the tunnel junction's mag…
Spin-orbit torques in locally and globally non-centrosymmetric crystals: Antiferromagnets and ferromagnets
One of the main obstacles that prevents practical applications of antiferromagnets is the difficulty of manipulating the magnetic order parameter. Recently, following the theoretical prediction [J. \v{Z}elezn\'y et al., PRL 113, 157201 (2014)], the electrical switching of magnetic moments in an antiferromagnet has been demonstrated [P. Wadley et al., Science 351, 587 (2016)]. The switching is due to the so-called spin-orbit torque, which has been extensively studied in ferromagnets. In this phenomena a non-equilibrium spin-polarization exchange coupled to the ordered local moments is induced by current, hence exerting a torque on the order parameter. Here we give a general systematic analys…