Abstract
In this paper we report low temperature measurements of the magnetic relaxation in a variety of magnetic systems. We show data for both logarithmic relaxation and exponential decay of magnetization. The existence of two relaxation regimes is demonstrated. At high temperatures both the viscosity (logarithmic decay) and the relaxation rate (exponential decay) depend on temperature. Below a few Kelvins the relaxation in both cases is independent of temperature. The crossover temperature between the two regimes is governed by the magnetic anisotropy constant in ferromagnets, depends on the external magnetic field and is in qualitative agreement with theoretical suggestions on quantum tunneling of magnetization.
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Tejada, J., Zhang, X. (1995). 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_7
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DOI: https://doi.org/10.1007/978-94-011-0403-6_7
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