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Quantum Tunneling of Magnetization in a Large Molecular Nanomagnet -- Approaching the Mesoscale

W. Wernsdorfer·M. Soler·D. N. Hendrickson·G. Christou
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Abstract

A Mn30 molecular cluster is established to be the largest single-molecule magnet (SMM) discovered to date. Magnetization versus field measurements show coercive fields of about 0.5 T at low temperatures. Magnetization decay experiments reveal an Arrhenius behavior and temperature-independent relaxation below 0.2 K diagnostic of quantum tunneling of magnetization through the anisotropy barrier.The quantum hole digging method is used to establish resonant quantum tunneling. These results demonstrate that large molecular nanomagnets,having a volume of 15 nm^3, with dimensions approaching the mesoscale can still exhibit the quantum physics of the microscale.

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W. Wernsdorfer, M. Soler, D. N. Hendrickson, G. Christou. 2003-06-11. Quantum Tunneling of Magnetization in a Large Molecular Nanomagnet -- Approaching the Mesoscale. https://arxiv.org/abs/cond-mat/0306303

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