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 ...

[1] Magnetostatic interactions have been investigated in an intergrown material consisting of 200-nm magnetite blocks separated by 30-nm-wide ulvöspinel lamellae. First-order reversal curve (FORC) measurements provide a direct measure of the interaction fields, giving a value for the full width at half maximum (FWHM) of 30 mT (at Hc = 20 mT). Hysteresis parameters are Mrs/Ms = 0.22, Hcr/Hc = 1....

i.e., that the free currents flow in closed loops. Likewise, the time derivative of the fourth Maxwell equation implies that Jfree has no time dependence in magnetostatics. Often, magnetostatics is taken to be the situation in which ∇ · Jfree = 0 and D, E and Jfree have no time dependence, without explicit assumption that B and H also have no time dependence. Discuss the possibility of waves of...

This paper poses two magnetostatic problems in cylindrical coordinates with different permeabilities for each region. In the first problem the boundary condition of the second kind is used while in the second one, the boundary condition of the third kind is utilized. These problems are solved using the finite element and finite difference methods. In second problem, the results of the finite di...

The interaction mechanism between transverse domain walls TDWs in Permalloy nanowires and artificially patterned traps is studied using high-sensitivity spatially resolved magneto-optical Kerr effect measurements and numerical simulations. T-shaped trap geometries are considered, where a DW traveling in the horizontal arm is pinned by the vertical arm. Pinning strengths as well as potential ene...

Magnetostatic Maxwell equations and the Landau-Lifshitz-Gilbert (LLG) equation are combined to a multiscale method, which allows to extend the problem size of traditional micromagnetic simulations. By means of magnetostatic Maxwell equations macroscopic regions can be handled in an averaged and stationary sense, whereas the LLG allows to accurately describe domain formation as well as magnetiza...