Sense anisotropy of the kink dynamics in an evolutionary equation with broken space symmetry

Abstract

A nonlinear diffusion-type evolutionary equation that describes the effect of sense anisotropy of velocity when the front of a solitary wave (kink) moves with unequal velocities in the forward and (when an external field reverses sign) backward directions is suggested. A prerequisite for such behavior is space symmetry breaking in the system. The equation is applied to describing the dynamics of 180° domain walls in ferromagnets with negative cubic crystalline anisotropy. The amount of the sense anisotropy effect in YIG may reach 20%.