Effects of notch shape on the magnetic domain wall motion in nanowires with in-plane or perpendicular magnetic anisotropy

Magnetic domain walls (DWs) in nanowires have been extensively investigated for potential applications in spintronic devices. For the precise storage of magnetic data, the control of DW pinning and depinning is critical. Here, we report upon the micromagnetic modeling results of the DW motion behaviors in notched or anti-notched nanowires possessing in-plane magnetic anisotropy (IMA) or perpendicular-to-the-plane magnetic anisotropy (PMA). In the nanowires with IMA, the energy of the DW in nanowires with anti-notches was lower compared to that of the nanowires with normal notches. Easier DW depinning motions were observed in the anti-notched nanowires. Unlike in the IMA case, the DW energy in the nanowires with PMA was lower with normal notches. Thus, the DW was able to move faster and easier through the normal notches compared to the anti-notches in the nanowire with the PMA at the same current density.

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