A one-dimensional model for wall motion coercivity in magneto-optic media

A numerical one-dimensional model for domain-wall structure in magneto-optic materials has been developed. It is assumed that the source of coercivity is a variation in micromagnetic parameters such as the exchange constant. A classical domain wall is placed at location of the change in the parameters and allowed to relax. Then, the coercivity is computed by slowly increasing a magnetic field until the wall breaks away from this well. In an illustrative example, a decrease in exchange, which permits a higher rate of spin rotation in the wall, distorts the classical domain-wall shape, and this distortion has to be reduced as the wall tries to break away.