Moving domain walls in ferromagnetic films with parallel anisotropy

Publisher Website
Google Scholar
Abstract
The dependence of wall mass and energy on wall velocity in thin Permalloy films is calculated by generalizing the Ritz model of Jakubovics (1978) for two-dimensional Bloch walls. In films 1000 Å thick, at low velocities, the wall mass is found to be about 52 times the value expected in bulk Permalloy. The mass increases with increasing velocity, v. Up to v≃3 × 104cm s−1 the increase is similar to that of a relativistic mass, namely proportional to (1−v 2/v ∞2)−½, with a critical velocity v ∞ ≈ 14.6 × 104 cm s −1. For v 3 × 104 cm s−1 the increase of mass with velocity becomes more rapid. The model breaks down for velocities above ≃ 6 × lO4cm s−1.
Keywords