Fig. 2: Magnetic domain disturbances caused by nano-indenter-induced deformation within single FeSi grains < 111 >.

a, d Magnetic force microscopy (MFM) images of the sample free-surface (||XY) taken prior to indenting at low (10⁻² s⁻¹) and high (10¹ s⁻¹) strain rates, respectively, revealing the topographically independent base state of the magnetic domain structure. b, e MFM images taken post-indentation at low (10⁻² s⁻¹) and high (10¹ s⁻¹) strain rates, respectively, in the same location as (a, d), respectively. Line scans of the MFM Phase (θ) are shown adjacent to the maps (a, b, d, e). c, f Atomic force microscopy (AFM) topography maps of the surfaces shown in (b, e), respectively, post-indentation. g, h Schematic representation of the annular regions extracted from the MFM images taken before and after indentation, used for calculating the mean areal MFM phase shift in (i). The coloured rings in (g) correspond with the extracted areas in (h) of the same colours. The central red circle in (g) represents the indentation footprint, which is extracted from the calculation of the annular regions in (h). i Plots of the mean areal MFM phase shift (Mθ_A) of the sample free-surface (||XY) before (square markers) and after (cross markers) indenting at low (10⁻² s⁻¹, blue lines) and high (10¹ s⁻¹, red lines) strain rates, revealing disparity in the magnetically disturbed areas – determined by the radial distance for the phase shift to reach the baseline (0°). The MFM colour bar applies to subfigures (a, b, d, e, g, h), indicating the centred MFM phase. The topography colour bar applies to sub-figures (c, f), indicating the surface height as measured from the mean surface plane. The coordinate system shown in (g) is the same for all subfigures. Scale bars in all subfigures, 10 μm. Source data for plots are provided as Source Data files.