. Kuteifan, bias where demonstrated using micromagnetic simulations, and further justified by an analytical model, which predicts the Walker breakdown field, peak velocity under field and current bias, and wall mobility in AFC systems. It was shown that it is possible to suppress the Walker breakdown limit for current-driven DW motion without a?ecting its mobility by using similar or identical values of the saturation magnetization in both layers of the AFC NW. This can be done for any value of the damping parameter ? or the non-adiabatic spin-transfer torque . ACKNOWLEDGMENTS This work was supported by the NSF grants DMR-1312750 and CCF-1117911, AIP Advances, vol.6, p.45103, 2016.

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