Influences of interfacial oxidization on surface magnetic energy, magnetic damping and spin-orbit-torques in Pt / ferromagnet / capping structures

Abstract

We investigate the effect of capping layer (CAP) on the interfacial magnetic anisotropy energy density (K_S), magnetic damping (α), and spin-orbit torques (SOTs) in heavy-metal (Pt) / ferromagnet (Co or Py) / CAP (MgO/Ta, HfOx, or TaN). At room temperature (RT) the CAP materials influence the effective magnitude of K_S, which is associated with a formation of interfacial magnetic oxides. The dynamical dissipation parameters of Co are considerably influenced by the CAP (especially MgO) while those of Py are not. This is possibly due to an extra magnetic damping via spin-pumping process across the Co/CoO interface and incoherent magnon generation (spin fluctuation) in the interfacial CoO. It is also observed that both anti-damping and field-like SOT efficiencies vary marginally with the CAP in the thickness ranges we examined. Our results reveal the crucial role of interfacial oxides on the perpendicular magnetic anisotropy, magnetic damping, and SOTs.

References in corpus (14)

• Magnetic switching by spin torque from the spin Hall effect
• Spin Torque Ferromagnetic Resonance Induced by the Spin Hall Effect
• Nonlocal magnetization dynamics in ferromagnetic heterostructures
• Switching of perpendicular magnetization by spin-orbit torques in the absence of external magnetic fields
• Magnetization switching by spin-orbit torque in an antiferromagnet/ferromagnet bilayer system
• Interface-Induced Phenomena in Magnetism
• Dependence of the Efficiency of Spin Hall Torque on the Transparency of Pt-Ferromagnetic Layer Interfaces
• Reversible control of Co magnetism by voltage induced oxidation
• Giant room temperature interface spin Hall and inverse spin Hall effects
• Spin Transport at Interfaces with Spin-Orbit Coupling: Formalism
• Spin-current probe for phase transition in an insulator
• Enhanced spin-orbit torque via modulation of spin current absorption
• On the origin of field-like spin-orbit torques in heavy metal-ferromagnet-oxide thin film heterostructures
• Relaxation mechanism driven by spin angular momentum absorption throughout antiferromagnetic phase transition in NiFe surface oxides