121 research outputs found
The angular dependence of spin-orbit torque in monolayer
In ferromagnetic systems lacking inversion symmetry, an applied electric
field can control the ferromagnetic order parameters through the spin-orbit
torque. The prototypical example is a bilayer heterostructure composed of a
ferromagnet and a heavy metal that acts as a spin current source. In addition
to such bilayers, spin-orbit coupling can mediate spin-orbit torques in
ferromagnets that lack bulk inversion symmetry. A recently discovered example
is the two-dimensional monolayer ferromagnet . In this work, we use
first-principles calculations to study the spin-orbit torque and ensuing
magnetic dynamics in this material. By expanding the torque versus
magnetization direction as a series of vector spherical harmonics, we find that
higher order terms (up to ) are significant and play important roles in
the magnetic dynamics. They give rise to deterministic, magnetic field-free
electrical switching of perpendicular magnetization.Comment: 8 pages (3 pages appendix), 7 figure
Implementation of a non-equilibrium Green's function method to calculate spin transfer torque
We present an implementation of the steady state Keldysh approach in a
Green's function multiple scattering scheme to calculate the non-equilibrium
spin density. This density is used to obtain the spin transfer torque in
junctions showing the magnetoresistance effect. We use our implementation to
study the spin transfer torque in metallic Co/Cu/Co junctions.Comment: 4 pages, 4 figure
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