Tunneling of magnetic domain walls in the quasirelativistic limit

An additional mechanism which increases the probability of tunneling of magnetic domain walls through defects of a crystal is discussed. In contrast to the thermally stimulated tunneling mechanisms described previously, which arise when the wall acquires additional energy from the thermal system of the crystal, the latter mechanism is produced by the change in the structure of the walls themselves at high energies, which changes the character of their interaction with defects. The results of analytic and numerical analyses of this effect are reported. A discussion and an interpretation of existing experimental results. (C) 1999 American Institute of Physics. [S1063-7834(99)02807-5].