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Quantum Thermoactivation of Nanoscale Magnets

D. A. Garanin
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Abstract

The integral relaxation time describing the thermoactivated escape of a uniaxial quantum spin system interacting with a boson bath is calculated analytically in the whole temperature range. For temperatures T much less than the barrier height ΔU, the level quantization near the top of the barrier and the strong frequency dependence of the one-boson transition probability can lead to the regularly spaced deep minima of the thermoactivation rate as a function of the magnetic field applied along the z axis.

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D. A. Garanin. 1998-05-05. Quantum Thermoactivation of Nanoscale Magnets. https://doi.org/10.1103/physreve.55.2569

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