Probing Ultrafast Magnetization Dynamics via Synthetic Axion Fields
Phys. Rev. Lett. 134, 246702 – Published 18 June, 2025
DOI: https://doi.org/10.1103/2rrr-glyn
Abstract
Spatial structuring of materials at subwavelength scales underlies the concept of metamaterials possessing exotic properties beyond those of the constituent media. Temporal modulation of material parameters enables further functionalities. Here, we show that high-frequency oscillations of spatially uniform magnetization generate an effective dynamic axion field embedding the amplitude and phase of magnetization oscillations. This allows one to map ultrafast magnetization dynamics using a probe signal with much lower frequency.
