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Crossover between Thermally Assisted and Pure Quantum Tunneling in Molecular Magnet Mn12-Acetate

Louisa Bokacheva·Andrew D. Kent·Marc A. Walters
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Abstract

The crossover between thermally assisted and pure quantum tunneling has been studied in single crystals of high spin (S=10) uniaxial molecular magnet Mn12 using micro-Hall-effect magnetometry. Magnetic hysteresis and relaxation experiments have been used to investigate the energy levels that determine the magnetization reversal as a function of magnetic field and temperature. These experiments demonstrate that the crossover occurs in a narrow (0.1 K) or broad (1 K) temperature interval depending on the magnitude of the field transverse to the anisotropy axis.

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Louisa Bokacheva, Andrew D. Kent, Marc A. Walters. 2001-01-02. Crossover between Thermally Assisted and Pure Quantum Tunneling in Molecular Magnet Mn12-Acetate. https://doi.org/10.1103/physrevlett.85.4803

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