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Abrupt Transition between Thermally-Activated Relaxation and Quantum Tunneling in a Molecular Magnet

K. M. Mertes·Y. Zhong·M. P. Sarachik·Y. Paltiel·H. Shtrikman·E. Zeldov·E. Rumberger·D. N. Hendrickson
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Abstract

We report Hall sensor measurements of the magnetic relaxation of Mn$_{12}$ acetate as a function of magnetic field applied along the easy axis of magnetization. Data taken at a series of closely-spaced temperatures between 0.24 K and 1.4 K provide strong new evidence for an abrupt ``first-order'' transition between thermally-assisted relaxation and magnetic decay via quantum tunneling.

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K. M. Mertes, Y. Zhong, M. P. Sarachik, Y. Paltiel, H. Shtrikman, E. Zeldov, E. Rumberger, D. N. Hendrickson. 2000-12-14. Abrupt Transition between Thermally-Activated Relaxation and Quantum Tunneling in a Molecular Magnet. https://doi.org/10.1209/epl%2Fi2001-00363-0

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