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arXiv · 1707.07009

Two-photon Lithography for 3D Magnetic Nanostructure Fabrication

Gwilym Williams·Matthew Hunt·Benedikt Boehm·Andrew May·Michael Taverne·Daniel Ho·Sean Giblin·Dan Read·John Rarity·Rolf Allenspach·Sam Ladak
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Abstract

Ferromagnetic materials have been utilised as recording media within data storage devices for many decades. Confinement of the material to a two dimensional plane is a significant bottleneck in achieving ultra-high recording densities and this has led to the proposition of three dimensional (3D) racetrack memories that utilise domain wall propagation along nanowires. However, the fabrication of 3D magnetic nanostructures of complex geometry is highly challenging and not easily achievable with standard lithography techniques. Here, by using a combination of two-photon lithography and electrochemical deposition, we show a new approach to construct 3D magnetic nanostructures of complex geometry. The magnetic properties are found to be intimately related to the 3D geometry of the structure and magnetic imaging experiments provide evidence of domain wall pinning at a 3D nanostructured junction.

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Gwilym Williams, Matthew Hunt, Benedikt Boehm, Andrew May, Michael Taverne, Daniel Ho, Sean Giblin, Dan Read, John Rarity, Rolf Allenspach, Sam Ladak. 2017-07-11. Two-photon Lithography for 3D Magnetic Nanostructure Fabrication. https://doi.org/10.1007/s12274-017-1694-0

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