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Absence of stable collinear configurations in Ni(001)ultrathin films: canted domain structure as ground state

G. Gubbiotti·G. Carlotti·M. G. Pini·P. Politi·A. Rettori·P. Vavassori·M. Ciria·R. C. O'Handley
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Abstract

Brillouin light scattering (BLS) measurements were performed for (17-120) Angstrom thick Cu/Ni/Cu/Si(001) films. A monotonic dependence of the frequency of the uniform mode on an in-plane magnetic field H was observed both on increasing and on decreasing H in the range (2-14) kOe, suggesting the absence of a metastable collinear perpendicular ground state. Further investigation by magneto-optical vector magnetometry (MOKE-VM) in an unconventional canted-field geometry provided evidence for a domain structure where the magnetization is canted with respect to the perpendicular to the film. Spin wave calculations confirm the absence of stable collinear configurations.

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G. Gubbiotti, G. Carlotti, M. G. Pini, P. Politi, A. Rettori, P. Vavassori, M. Ciria, R. C. O'Handley. 2002-04-03. Absence of stable collinear configurations in Ni(001)ultrathin films: canted domain structure as ground state. https://doi.org/10.1103/physrevb.65.214420

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