We develop a model for studying MQC in small antiferromagnetic particles in terms of two spins representing the total moment on two sublattices. The model can treat external magnetic fields and unequal sublattice moments, and is specifically designed to capture topological effects arising from the Berry phase in the spin action. The tunneling rate is calculated for several configurations; both the usual WKB exponent and the topological term depend on both the field and excess moment.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering