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Tunneling Rate for Superparamagnetic Particles by the Instanton Method

E. H. Martins Ferreira·M. C. Nemes
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Abstract

We derive the tunneling rate for paramagnetic molecules in the context of a collective spin model. By means of path integral methods an analytical expression is derived. Given the very large spins in question (s ~ 3000 hbar), the observation of magnetization changes due to pure unitary tunnel effects is unlikely.

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E. H. Martins Ferreira, M. C. Nemes. 2002-07-31. Tunneling Rate for Superparamagnetic Particles by the Instanton Method. https://doi.org/10.1016/s0378-4371(02)00620-9

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