Fig. 5: Micromagnetic simulations showing the reversal process of the magnetic disks upon application of –25 V.
From: Magneto-ionic vortices: voltage-reconfigurable swirling-spin analog-memory nanomagnets
Simulated hysteresis loops are shown for 280-nm diameter magnetic disks where the thicknesses and magnetic parameters were chosen to capture the reversal behavior of (a) a short-term voltage treatment (thickness 2 nm, MS = 400 emu cm−3, Ku = 2.5\(\times\)105 erg cm−3), (b) a mid-term voltage treatment (thickness 8 nm, MS = 500 emu cm−3, Ku = 3.5\(\times\)105 erg cm-3), and (c) long-term voltage treatment (thickness 12 nm, MS = 550 emu cm−3, Ku = 6.0\(\times\)105 erg cm-3). The hysteresis loops shown on the left are an average of 10 runs (see Supplementary Fig. 10 for details), and the images on the right show spin distributions (top) and calculated MFM images (bottom) at selected fields for a representative run. Blue and purple dashed lines mark the values of annihilation HA and coercive fields HC, respectively.
