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arXiv · 1403.6885

Driving ferromagnets into a critical region of a magnetic phase diagram

B. Y. Mueller·B. Rethfeld
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Abstract

Exciting a ferromagnetic sample with an ultrashort laser pulse leads to a quenching of the magne- tization on a subpicosecond timescale. On the basis of the equilibration of intensive thermodynamic variables we establish a powerful model to describe the demagnetization dynamics. We demonstrate that the magnetization dynamics is mainly driven by the equilibration of chemical potentials. The minimum of magnetization is revealed as a transient electronic equilibrium state. Our method iden- tifies the slowing down of ultrafast magnetization dynamics by a critical region within a magnetic phase diagram.

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B. Y. Mueller, B. Rethfeld. 2014-03-26. Driving ferromagnets into a critical region of a magnetic phase diagram. https://doi.org/10.1103/physrevb.90.144420

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