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Nuclear spin dynamics in the quantum regime of a single-molecule magnet

Andrea Morello·Oleg N. Bakharev·Hans B. Brom·Roberta Sessoli·L. Jos de Jongh
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Abstract

We show that the nuclear spin dynamics in the single-molecule magnet Mn12-ac below 1 K is governed by quantum tunneling fluctuations of the cluster spins, combined with intercluster nuclear spin diffusion. We also obtain the first experimental proof that - surprisingly - even deep in the quantum regime the nuclear spins remain in good thermal contact with the lattice phonons. We propose a simple model for how T-independent tunneling fluctuations can relax the nuclear polarization to the lattice, that may serve as a framework for more sophisticated theories.

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Andrea Morello, Oleg N. Bakharev, Hans B. Brom, Roberta Sessoli, L. Jos de Jongh. 2004-11-16. Nuclear spin dynamics in the quantum regime of a single-molecule magnet. https://doi.org/10.1103/physrevlett.93.197202

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