New Journal of Physics (Jan 2014)
Hysteresis-free switching between vortex and collinear magnetic states
Abstract
We demonstrate a lossless switching between vortex and collinear magnetic states in circular FePd disks arranged in a square lattice. Above a bifurcation temperature $\left( {{T}_{\text{e}}} \right)$ we show that thermal fluctuations are enough to facilitate flipping between the two distinctly different magnetic states. We find that the temperature dependence of the vortex annihilation and nucleation fields can be described by a simple power law relating them to the saturation magnetization.
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