Abstract
It is shown how large domain walls, containing ≥ spins, can behave as quantum objects at low temperatures. They move quantum diffusively, and exhibit macroscopic tunneling from defect pinning centers. The dissipation is calculated and shown to be very small; it does not involve the usual Caldeira-Leggett environmental couplings. The theory can also be used to treat smaller single-domain-wall behavior.
- Received 4 September 1990
DOI:https://doi.org/10.1103/PhysRevLett.66.2802
©1991 American Physical Society