Magnetic shift registers in which data writing and reading is accomplished
by moving the magnetic domain walls by electric current. Various
embodiments of domain wall nodes or anchors that stabilize a domain wall
are provided. In some embodiments, the wall anchors are elements separate
from the magnetic track. In other embodiments, the wall anchors are
disturbances in the physical configuration of the magnetic track. In
still other embodiments, the wall anchors are disturbances in the
material of the magnetic track.