Direct imaging of nanoscale field-driven domain wall oscillations in Landau structures

Abstract

We demonstrate a direct imaging approach to capture the DW oscillation with nanoscale resolution and study its dependency on various physical parameters. This study confirms that the DW oscillations behave as a damped harmonic oscillator.

2024 roadmap on magnetic microscopy techniques and their applications in materials science

“…However, side-band or A-MFM enables the imaging of temporally oscillating processes, such as the magnetic excitation of superparamagnetic particles [166] or high-frequency fields from a recording head [167]. Recently, time-averaged MFM has also been used to image spatially varying processes, including nanoscale domain wall movements oscillating at frequencies up to 1 kHz, with the potential for measuring at hundreds of kHz in the future [168].…”

“…Dynamic phenomena studied by MFM: existing time-averaged and time-resolved MFM techniques allow studying fundamental aspects of nanoscale domain wall oscillations (figure 10(r)) [168]. These are not only relevant in novel magnetic nanodevices such as domain wall resonators [190] and memory devices, but also in sensor materials based on a domain wall-based magneto impedance effect [191] and in classical soft magnetic materials for transformer applications.…”

“…(r) Imaging dynamic phenomena: domain wall oscillation in a permalloy Landau structure. (i) Demagnetized state, (ii) real-time imaging of the quasi-static domain wall oscillating with 0.01 Hz (iii) static DW in the x-t plane, (iv) time-averaged imaging of the DW oscillating with a frequency of 1 kHz (µ0Hac = 0.10 mT) in the x-t plane[168].…”