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arXiv · 1702.02820

Transient spin dynamics in a single-molecule magnet

Henning Hammar·Jonas Fransson
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Abstract

We explore the limitations and validity of semi-classically formulated spin equations of motion. Using a single-molecule magnet as a test model, we employ three qualitatively different approximation schemes. From a microscopic model, we derive a generalized spin equation of motion in which the parameters have a non-local time-dependence. This dynamical equation is simplified to the Landau-Lifshitz-Gilbert equation with i) time-dependent, and ii) time-independent parameters. We show that transient dynamics is essentially non-existing in the latter approximation, while the former breaks down in the regime of strong coupling between the spin and the itinerant electrons.

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Henning Hammar, Jonas Fransson. 2017-12-05. Transient spin dynamics in a single-molecule magnet. https://doi.org/10.1103/physrevb.96.214401

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