Nonuniform switching of the perpendicular magnetization in a spin-torque-driven magnetic nanopillar

作者：Bernstein David P^*; Braeuer Bjoern; Kukreja Roopali; Stoehr Joachim; Hauet Thomas; Cucchiara Julien; Mangin Stephane; Katine Jordan A; Tyliszczak Tolek; Chou Kang W; Acremann Yves

来源：Physical Review B, 2011, 83(18): 180410.

DOI：10.1103/PhysRevB.83.180410

Time-resolved scanning transmission x-ray microscopy measurements were performed to study the current-induced magnetization switching mechanism in nanopillars exhibiting strong perpendicular magnetic anisotropy. This technique provides both short-time (70 ps) and high-spatial (25 nm) resolutions. Direct imaging of the magnetization demonstrates that, after an incubation time of similar to 1.3 ns, a 100 x 300 nm(2) ellipsoidal device switches in similar to 1 ns via a central domain nucleation and opposite propagation of two domain walls toward the edges. High domain-wall velocities on the order of 100 m/s are measured. Micromagnetic simulations are shown to be in good agreement with experimental results and provide insight into magnetization dynamics during the incubation and reversal periods.

• 出版日期2011-5-10