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Depinning of domain walls in permalloy nanowires with asymmetric notches.

ABSTRACT: Effective control of the domain wall (DW) motion along the magnetic nanowires is of great importance for fundamental research and potential application in spintronic devices. In this work, a series of permalloy nanowires with an asymmetric notch in the middle were fabricated with only varying the width (d) of the right arm from 200?nm to 1000?nm. The detailed pinning and depinning processes of DWs in these nanowires have been studied by using focused magneto-optic Kerr effect (FMOKE) magnetometer, magnetic force microscopy (MFM) and micromagnetic simulation. The experimental results unambiguously exhibit the presence of a DW pinned at the notch in a typical sample with d equal to 500?nm. At a certain range of 200?nm?

SUBMITTER: Gao Y

PROVIDER: S-EPMC5013472 | biostudies-literature | 2016 Sep

REPOSITORIES: biostudies-literature

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Depinning of domain walls in permalloy nanowires with asymmetric notches.

Gao Y Y You B B Ruan X Z XZ Liu M Y MY Yang H L HL Zhan Q F QF Li Z Z Lei N N Zhao W S WS Pan D F DF Wan J G JG Wu J J Tu H Q HQ Wang J J Zhang W W Xu Y B YB Du J J

Scientific reports 20160907

Effective control of the domain wall (DW) motion along the magnetic nanowires is of great importance for fundamental research and potential application in spintronic devices. In this work, a series of permalloy nanowires with an asymmetric notch in the middle were fabricated with only varying the width (d) of the right arm from 200 nm to 1000 nm. The detailed pinning and depinning processes of DWs in these nanowires have been studied by using focused magneto-optic Kerr effect (FMOKE) magnetomete ...[more]

PMID: 27600627

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