Fig. 4: Nucleation picture in permanent magnets.
From: Role of atomic-scale thermal fluctuations in the coercivity
Schematic pictures of a, c energy landscape and b, d spin configuration in the magnetization reversal processes at low-temperature limit. a, b Heisenberg type spin model with uniaxial magnetic anisotropy. c, d Ising type. The energy landscapes under several magnetic fields are drawn (the lowest line is for Hz = 0). Dotted lines are the reverse magnetic field terms ÎĽ0HzMz and blue points are the top of the energy barriers.
