Magneto-mechanical resonance of a single superparamagnetic microbead trapped by a magnetic domain wall

TitleMagneto-mechanical resonance of a single superparamagnetic microbead trapped by a magnetic domain wall
Publication TypeJournal Article
Year of Publication2012
AuthorsRapoport, E, Beach, GSD
JournalJournal of Applied Physics
Volume111
Issue7
Pagination07B310
Date Published2012/04/01/
Abstract

Magnetic domain walls in ferromagnetic tracks can be used to trap and transport superparamagnetic beads for lab-on-a-chip applications. Here it is shown that the magnetostatic binding between a domain wall and a superparamagnetic bead suspended in a host fluid leads to a distinct magneto-mechanical resonance under application of a sinusoidal driving field. The characteristic resonant frequency depends on the ratio of the magnetostatic binding force to the viscous drag on the bead. This resonance has been experimentally detected for a single trapped superparamagnetic bead using an optical detection technique. (C) 2012 American Institute of Physics. [doi:10.1063/1.3672406]