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Escape-Rate Crossover between Quantum and Classical Regimes in Molecular Magnets: A Diagonalization Approach

Gwang-Hee Kim·E. M. Chudnovsky
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Abstract

We have studied numerically the quantum-classical crossover in the escape-rate for an uniaxial spin system with an arbitrarily directed field. Using the simple quantum transition-state theory, we have obtained the boundary separating the first- and the second-order crossover and the escape-rate in the presence of the transverse and longitudinal field. The results apply to the molecular nanomagnet, ${\rm Mn_{12}}$.

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Gwang-Hee Kim, E. M. Chudnovsky. 2000-05-31. Escape-Rate Crossover between Quantum and Classical Regimes in Molecular Magnets: A Diagonalization Approach. https://doi.org/10.1209/epl%2Fi2000-00110-7

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