Topological Quenching of Spin Tunneling in Mn12-acetate Molecules
نویسندگان
چکیده
We investigate the topological quenching of spin tunneling in Mn12-acetate molecules with an applied magnetic field along the hard axis. The model Hamiltonian describing this system has a fourth-order term due to the tetragonal anisotroy. We treat this model using the discrete phase integral formalism in which the Schrödinger equation corresponding to the Hamiltonian becomes a nine-term recursion relation. We solve this recursion relation and find that the tunnel splitting is quenched at certain values of the applied field. We also present a qualitative treatment based on the instanton approach. 75.10Dg, 03.65.Db, 03.65.Sq, 75.45.+j, 75.50.Xx Typeset using REVTEX
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