Abstract
It is possible to observe experimental behavior that might be taken to be indicative of quantum tunneling of magnetization but is instead a manifestation of purely classical relaxation. We discuss a number of results that have a bearing on our ability to make such a discrimination, including sample characterization using scaling laws in the magnetic viscosity and the dynamical susceptibility (with expressions for both the classical and quantum regimes), temperature fluctuations, and domain wall tunneling across a domain wall junction for both ferromagnets and antiferromagnets. We also stress the importance of further theoretical and experimental studies of dissipation in magnetic relaxation, not only because of its strong effect on the WKB exponent, but also because of its effect on the strong temperature dependence of the prefactor in thermal relaxation.
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Gunther, L. (1995). On the Search for Quantum Tunneling of Magnetization. In: Gunther, L., Barbara, B. (eds) Quantum Tunneling of Magnetization — QTM ’94. NATO ASI Series, vol 301. Springer, Dordrecht. https://doi.org/10.1007/978-94-011-0403-6_23
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DOI: https://doi.org/10.1007/978-94-011-0403-6_23
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