Fig. 3: Magnetization reversal study of Penrose P2 and P3 artificial magnetic quasicrystals (AMQs) via X-ray photoemission electron microscopy (XPEEM).
a–f XPEEM topography images for six different quasicrystals as labeled in the graphs. Bright (dark) regions correspond to magnetic (non-magnetic) material. The scale bar given in (a) corresponds to 1 μm. The arrow in (a) represents the X-ray direction and the magnetic field direction. Selected magnetic images of remnant states using XPEEM after applying different field values μoH (given in parenthesis) for (g) P2A (32.5 mT), (h) P2B (41.6 mT), (i) P2C (42.64 mT), (j) P3A (36.4 mT), (k) P3B (42.9 mT), and (l) P3C (48.1 mT) representing the switching of 44%, 51%, 46%, 56%, 44%, and 55% type I nanobars, respectively. Blue (red) colors represent magnetization parallel (opposite) to the X-ray direction. Blue color indicates a reversed nanobar. The images represent the states attained when about 50% of Type I nanobars switched. Notice the weak contrast in case of nanobars which do not point along the X-ray direction. m–r Charge model (CM) analysis of the X-ray magnetic circular dichroism (XMCD) experimental data shown in (g)–(l). The green and orange filled circles at the vertices represent positive and negative vertex charges, respectively. Here the circles with smallest and largest diameter and intensity represent charge ∣Q∣ = 0 and ∣Q∣ = 5, respectively. When quasicrystals consist of disconnected nanobars a large charge of up to ∣Q∣ = 5 can be found. The magnetic configurations of P2 and P3 tilings in the as-grown state are displayed in Supplementary Fig. 1.
