Time-resolved imaging of three-dimensional nanoscale magnetization dynamics

Abstract

The ability to experimentally map the three-dimensional structure and dynamics in bulk and patterned three-dimensional ferromagnets is essential both for understanding fundamental micromagnetic processes, as well as for investigating technologically-relevant micromagnets whose functions are connected to the presence and dynamics of fundamental micromagnetic structures, such as domain walls and vortices. Here, we demonstrate time-resolved magnetic laminography, a technique which offers access to the temporal evolution of a complex threedimensional magnetic structure with nanoscale resolution. We image the dynamics of the complex three-dimensional magnetization state in a two-phase bulk magnet with a lateral spatial resolution of 50 nm, mapping the transition between domain wall precession and the dynamics of a uniform magnetic domain that is attributed to variations in the magnetization state across the phase boundary. The capability to probe three-dimensional magnetic structures with temporal resolution paves the way for the experimental investigation of novel functionalities arising from dynamic phenomena in bulk and three-dimensional patterned nanomagnets.One Sentence Summary: Nanoscale dynamics of a three-dimensional magnetic system are revealed with pump-probe magnetic laminography. Main Text:Understanding and controlling the dynamic response of magnetic materials with a threedimensional magnetization distribution is important both fundamentally and for technological applications. From a fundamental point of view, the internal structure and reversal phenomena in known bulk materials still need to be mapped [1], along with the dynamic properties of topological structures such as vortices [2], magnetic singularities [3] or skyrmion lattices [4]. From a technological point of view, the response of inductive materials to magnetic fields and spin-polarized currents is essential for magnetic sensors and data storage devices [5].In addition to bulk systems, curved and three-dimensional magnetic structures such as nanotubes and nanowire-based systems have been predicted to exhibit dynamic properties markedly

Electroless Deposition of Ni–Fe Alloys on Scaffolds for 3D Nanomagnetism

“…[ 1,2,3,12 ] The combination with recent developments in 3D magnetic characterization methods such as 3D dark‐field MOKE and 3D magnetic X‐ray imaging methods, could lead to new insights in the growing field of 3D nanomagnetism, including the development of novel applications such as high‐density storage devices and 3D logic elements. [ 38–45 ]…”

Imaging three-dimensional magnetic systems with x-rays

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LamNI – an instrument for X-ray scanning microscopy in laminography geometry

“…PyXL has also proven useful for measurements with magnetic contrast. Donnelly et al (2020) have demonstrated time-resolved measurements of magnetization dynamics in a microdisc using LamNI, where the laminography geometry has also proven to be advantageous compared with tomography in the ease of implementing magnetic field excitations. The spatial and temporal resolution achieved was 50 nm and 70 ps, respectively, the latter limited by the timing structure of the synchrotron source.…”