Domain Wall Motion in the Presence of Nuclear Spins

M. Dube, P. C. E. Stamp

Published 1999-08-28Version 1

We investigate the motion of a domain wall in the presence of a dynamical hyperfine field. At temperature T high compared to the hyperfine coupling, the nuclear spins create a spatially random potential landscape, with dynamics dictated by the nuclear relaxation time $T_2$. The distribution of the domain wall relaxation times (both in the thermal and quantum regimes) can show a long tail, characteristic of stochastic processes where rare events are important. Here, these are due to occasional strong fluctuations in the nuclear spin polarisation.