Switching fields and magnetostatic interactions of thin film magnetic nanoelements

Kirk, K.J.; Chapman, J. N.; Wilkinson, C. D. W.

doi:10.1063/1.119602

Cited by 192 publications

(77 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The reversal appears to proceed by a nucleation process, with the end caps serving as the seeds for heterogeneous nucleation. The initiation of the switching from the end caps is similar to results for reversal induced by applied fields greater than H c in experiments, 25 and simulations with T =0 K where reversal begins at the end caps 22,26 or corners.…”

Section: B Switching In Constant Fieldsupporting

confidence: 63%

Langevin simulation of thermally activated magnetization reversal in nanoscale pillars

2001

View full text Add to dashboard Cite

Numerical solutions of the Landau-Lifshitz-Gilbert micromagnetic model incorporating thermal fluctuations and dipole-dipole interactions (calculated by the Fast Multipole Method) are presented for systems composed of nanoscale iron pillars of dimension 9 nm × 9 nm × 150 nm. Hysteresis loops generated under sinusoidally varying fields are obtained, while the coercive field is estimated to be 1979 ± 14 Oe using linear field sweeps at T = 0 K. Thermal effects are essential to the relaxation of magnetization trapped in a metastable orientation, such as happens after a rapid reversal of an external magnetic field less than the coercive value. The distribution of switching times is compared to a simple analytic theory that describes reversal with nucleation at the ends of the nanomagnets. Results are also presented for arrays of nanomagnets oriented perpendicular to a flat substrate. Even at a separation of 300 nm, where the field from neighboring pillars is only ∼ 1 Oe, the interactions have a significant effect on the switching of the magnets.

show abstract

Section: B Switching In Constant Fieldsupporting

confidence: 63%

Langevin simulation of thermally activated magnetization reversal in nanoscale pillars

2001

View full text Add to dashboard Cite

show abstract

“…The elliptical pad shown in Fig. 1(a) has a coercivity of around 10 Oe, and this is used to nucleate DWs which propagate along the wire and are pinned at the constriction, while the pointed end suppresses DW formation at the other end of the wire [22]. After reversal from saturation, a sharp drop in resistance is observed at 10 Oe in Fig.…”

mentioning

confidence: 91%

Dependence of Domain-Wall Depinning Threshold Current on Pinning Profile

et al. 2009

View full text Add to dashboard Cite

Use policyThe full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-pro t purposes provided that:• a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders.Please consult the full DRO policy for further details.

show abstract

“…While in bulk systems the number of available states tends to be large, as the size is reduced the separation in energy between the different magnetic states becomes progressively larger, leading to the stabilization of a few relatively simple magnetic conf gurations that tend to ref ect the geometrical symmetry of the element. For example, mesoscopic square elements tend to fall into the quadrant, or Landau-Lifshitz, state [24][25][26][27], while discs tend to fall into the vortex state [19,[28][29][30], even though other high symmetry states are accessible in these geometries, such as the diamond and triangle state in disc elements [30][31][32][33][34] or other less symmetric states in squares [35,36]. As mentioned previously, micrometre size magnetic rings fall into two distinct magnetic states during the magnetization process.…”

Section: Energetics Of Equilibrium Statesmentioning

confidence: 99%

Ferromagnetic Nanorings

et al. 2007

View full text Add to dashboard Cite

Ferromagnetic metal rings of nanometre range widths and thicknesses exhibit fundamentally new spin states, switching behaviour and spin dynamics, which can be precisely controlled via geometry, material composition and applied f eld. Following the discovery of the 'onion state', which mediates the switching to and between vortex states, a range of fascinating phenomena has been found in these structures. In this overview of our work on ring elements, we f rst show how the geometric parameters of ring elements determine the exact equilibrium spin conf guration of the domain walls of rings in the onion state, and we show how such behaviour can be understood as the result of the competition between the exchange and magnetostatic energy terms. Electron transport provides an extremely sensitive probe of the presence, spatial location and motion of domain walls, which determine the magnetic state in individual rings, while magneto-optical measurements with high spatial resolution can be used to probe the switching behaviour of ring structures with very high sensitivity. We illustrate how the ring geometry has been used for the study of a wide variety of magnetic phenomena, including the displacement of domain walls by electric currents, magnetoresistance, the strength of the pinning potential introduced by nanometre size constrictions, the effect of thermal excitations on the equilibrium state and the stochastic nature of switching events.

show abstract

Switching fields and magnetostatic interactions of thin film magnetic nanoelements

Cited by 192 publications

References 5 publications

Langevin simulation of thermally activated magnetization reversal in nanoscale pillars

Langevin simulation of thermally activated magnetization reversal in nanoscale pillars

Dependence of Domain-Wall Depinning Threshold Current on Pinning Profile

Ferromagnetic Nanorings

Contact Info

Product

Resources

About