Dynamic phase transitions in thin ferromagnetic films

Hyunbum Jang; Malcolm J. Grimson; Carol K. Hall

doi:10.1103/physrevb.67.094411

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Dynamic phase transitions in thin ferromagnetic films

Hyunbum Jang·Malcolm J. Grimson·Carol K. Hall

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Abstract

Monte Carlo simulations have been used to investigate the dynamic phase behavior of a classical Heisenberg spin system with a bilinear exchange anisotropy in a planar thin film geometry. Studies of the field amplitude, frequency and temperature dependence show dynamic phase transitions in films subject to a pulsed oscillatory external field. Thin films with competing surface fields show separate and distinct dynamic phase transitions for the bulk and surface layers of the film. Between the two transitions, a mixed state with coexisting dynamically ordered and dynamically disordered phases is observed in the film. In contrast, the free film with no surface fields shows a single dynamic phase transition as in a bulk system.

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Hyunbum Jang, Malcolm J. Grimson, Carol K. Hall. 2003-02-06. Dynamic phase transitions in thin ferromagnetic films. https://doi.org/10.1103/physrevb.67.094411

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