Current-driven vortex domain wall dynamics by micromagnetic simulations

Physical review. B, Condensed matter (Impact Factor: 3.77). 05/2006; 73(18). DOI: 10.1103/PhysRevB.73.184408
Source: arXiv

ABSTRACT Current-driven vortex wall dynamics is studied by means of a two-dimensional analytical model and micromagnetic simulation. By constructing a trial function for the vortex wall in the magnetic wire, we analytically solve for domain wall velocity and deformation in the presence of the current-induced spin torque. A critical current for the domain wall transformation from the vortex wall to the transverse wall is calculated. A comparison between the field- and current-driven wall dynamics is carried out. Micromagnetic simulations are performed to verify our analytical results.

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