Molecular Crystals and Liquid Crystals Science and Technology. Section A. Molecular Crystals and Liquid Crystals, Vol.342, 279-284, 2000
Theoretical studies on quantum tunneling of spins in cluster of clusters
In this work, we consider a cluster, which consists of small clusters with an anisotropy energy and suppose that the Hamiltonian of each cluster in the cluster is represented by the nonlinear sigma model. We apply a single spin model to the model clusters and calculate the time evolution of spin wavepacket. We demonstrate a magnetic field induced tunneling and elucidate its mechanism.