The Energy and General Translation Force of Cylindrical Magnetic Domains

Abstract

In this paper we compute the change in the energy of a uniformly magnetized uniaxial platelet produced by the introduction of a cylindrical domain. Differentiation of the energy expression yields the translational force produced by gradients in plate thickness, material composition, or temperature. The force expressions provide a means for estimating the effect of gradients in these parameters on the margins of domain devices. Equating the sum of the gradient produced forces to the drag force yields a general domain velocity expression. The various results are presented in both graphical and tabular form.

Unidirectional Thermal Effects in Current-Induced Domain Wall Motion

“…A thermodynamic force, the gradient of DW energy caused by the temperature gradient, has been known for a long time [28]. As all magnetic energies disappear at the Curie temperature, it is expected to push the DW towards the hotter part [5], as observed here.…”

Application of field emission in prolate-spheroidal coordinate in heat-assisted magnetic probe recording

“…When the bias voltage exceeds the work function like our work, field emission replaces the tunneling. The classical theory of field emission is based on the one-dimensional, planar Fowler--Nordheim equation [14]. In this model, the current density is expressed as following:…”

“…Thus, this medium is strongly coupled. Based on a theory of magnetic domain dynamics on perpendicular strongly coupled media [14][15][16][17], the minimum stable domain size is calculated as 70 nm for this film.…”

Data retention in organic ferroelectric resistive switches

“…The driving force for retracting from the semiconductor domains is counteracted by the energy penalty associated with increasing the perimeter of the depolarized area -the latter mechanism is responsible for the instability of inverted domains below a critical size upon polarization reversal of a ferroelectric. [21][22][23][24] Growth of the depolarized area is therefore self-limiting. Once the stray field at its perimeter sits predominantly in the ferroelectric phase, there is no longer a driving force for further depolarization.…”

“…As mentioned above there are two contributions to the total energy of the system: the domain wall (DW) energy and the electrostatic (E) energy. Hence the total energy of the simulated system is calculated as [21][22][23]:…”