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arXiv · 0803.3038

Response of a ferrofluid to traveling-stripe forcing

A. Beetz·C. Gollwitzer·R. Richter·I. Rehberg
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Abstract

We observe the dynamics of waves propagating on the surface of a ferrofluid under the influence of a spatially and temporarily modulated field. In particular, we excite plane waves by a travelling lamellar modulation of the magnetization. By this external driving both the wavelength and the propagation velocity of the waves can be controlled. The amplitude of the excited waves exhibits a resonance phenomenon similar to that of a forced harmonic oscillator. Its analysis reveals the dispersion relation of the free surface waves, from which the critical magnetic field for the onset of the Rosensweig instability can be extrapolated.

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A. Beetz, C. Gollwitzer, R. Richter, I. Rehberg. 2008-03-20. Response of a ferrofluid to traveling-stripe forcing. https://doi.org/10.1088/0953-8984%2F20%2F20%2F204109

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