3D Interconnected Magnetic Nanowire Networks as Potential Integrated Multistate Memristors

Abstract

Interconnected magnetic nanowire (NW) networks offer a promising platform for three-dimensional (3D) information storage and integrated neuromorphic computing. Here we report discrete propagation of magnetic states in interconnected Co nanowire networks driven by magnetic field and current, manifested in distinct magnetoresistance (MR) features. In these networks, when only a few interconnected NWs were measured, multiple MR kinks and local minima were observed, including a significant minimum at a positive field during the descending field sweep. Micromagnetic simulations showed that this unusual feature was due to domain wall (DW) pinning at the NW intersections, which was confirmed by off-axis electron holography imaging. In a complex network with many intersections, sequential switching of nanowire sections separated by interconnects was observed, along with stochastic characteristics. The pinning/depinning of the DWs can be further controlled by the driving current density. These results illustrate the promise of such interconnected networks as integrated multistate memristors.

Voltage-Controlled ON–OFF-Switching of Magnetoresistance in FeOx/Fe/Au Aerogel Networks

“…AMR has a lower sensitivity than giant magnetoresistance and TMR effects but offers the advantage of a much easier fabrication not involving complex layer stacks. This makes AMR attractive for novel schemes for printed electronics, flexible and 3D magnetosensors, , and 3D information storage . From the present proof-of-principle on iron-based magneto-ionic structures, a transfer to nickel or nickel–iron alloy structures exhibiting much larger AMR than iron can be envisioned …”

“…The nanoscale morphology of the iron hydroxide/iron/gold aerogel networks will not be problematic for many emerging magnetic sensor applications; some of these already employ magnetic nanoparticles or nanoflakes with irregular geometry. , Emerging concepts for 3D information storage and neuromorphic computing may require more organization on the nanoscale. Here, a transfer of the self-terminating electrodeposition and the magneto-ionic control to more defined 3D nanostructures, such as interconnected nanowire networks, is a perspective.…”

“…Magnetoresistance (MR) is a key material property for advanced magnetic information storage and sensors. − So far, MR has been mainly studied and applied in thin film geometries. MR in three-dimensional (3D) nanostructures is exciting from both fundamental and application points of view. − The MR of nanowires, nanotubes, and their arrays, for example, serves as a sensitive measure of their magnetic states − and is discussed for magnetic sensing for e-skins and printed electronics, as well as for novel concepts for 3D magnetic information-storage and neuromorphic computing. − …”

A perfect conical nanoshape meets large magnetocrystalline anisotropy: unusual magnetic configurations

“…5,6 Based on these new phenomena, the magnetic nanowires potentially unlock some advanced applications such as information storage, microwave absorption, and energy storage and conversion. [7][8][9][10][11][12] For a magnetic nanowire, the magnetic configurations are mainly influenced by shape anisotropy, magnetocrystalline anisotropy, and exchange interaction. The configurations then largely determine the magnetization reversal including the coherent rotation process, transverse domain wall expansion, and curling mode.…”

“…5,6 Based on these new phenomena, the magnetic nanowires potentially unlock some advanced applications such as information storage, microwave absorption, and energy storage and conversion. 7–12…”