Nonlinear dynamics of a single ferrofluid-peak in an oscillating magnetic field

✍ Scribed by Thomas Mahr; Ingo Rehberg

• Publisher: Elsevier Science
• Year: 1998
• Tongue: English
• Weight: 814 KB
• Volume: 111
• Category: Article
• ISSN: 0167-2789
• DOI: 10.1016/s0167-2789(97)80019-x

✦ Synopsis

If a magnetic field normal to the surface of a magnetic fluid is increased beyond a critical value a spontaneous deformation of the surface arises (normal field instability). The instability is subcritical and leads to peaks of a characteristic shape. We investigate the neighborhood of this instability experimentally under the influence of a temporal modulation of the magnetic field. We use a small vessel, where only one peak arises. The modulation can either be stabilizing or destabilizing, depending on the frequency and amplitude. We observe a cascade of odd-numbered response-periods up to period 11, and also a domain of even-numbered periods. We propose a minimal model involving a cutoff-conditon which captures the essence of the experimental observations.