Topological Quenching of Spin Tunneling in Mn_12-acetate Molecules

Chang-Soo Park; Anupam Garg

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Topological Quenching of Spin Tunneling in Mn_12-acetate Molecules

Chang-Soo Park·Anupam Garg

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Abstract

We investigate the topological quenching of spin tunneling in Mn_12-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 anisotropy. We treat this model using the discrete phase integral formalism in which the Schrodinger 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.

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Chang-Soo Park, Anupam Garg. 2000-09-29. Topological Quenching of Spin Tunneling in Mn_12-acetate Molecules. https://arxiv.org/abs/cond-mat/0009478

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