The role of dipole coupling in multilayers

Abstract

Articles you may be interested inCross-relaxation between macromolecular and solvent spins: The role of long-range dipole couplings Role of dynamic exchange coupling in magnetic relaxations of metallic multilayer films (invited) J. Appl. Phys. 93, 7545 (2003); 10.1063/1.1543852Dipoleexchange spin wave spectra of exchangecoupled magnetic multilayers calculated by transfer matrix formalism Thii work considers the role of magnet.ic dipole coupling in multilayers typically comprising a ferromagnetic material separated by a nonmagnetic metal spacer, e.g., NiFe!Ta. It has been suggested previously that dipolar fields may play an important role in the coupling of magnetic layers through a nonmagnetic spacer, in particular where surface roughness at the interface is significant. This work considers a first-order calculation of the dipole coupling energy and magnetic field between two adjacent layers. It is shown that dipole coupling energies originating from surface corrugations can behave in the same manner as a coercive field in terms of dependence on nonmagnetic spacer thickness and the degree of roughness. Interestingly, calculations also show that both ferromagnetic-and antiferromagnetic-like coupling can be explained in terms of this model. The role of the spacer thickness, magnetic layer thickness, and the form of the roughness is discussed.

Magnetic coupling in metallic granular systems

“…Finally, it is interesting to notice that, similarly to the case of correlated roughness in multilayers, 18,19 it is possible to obtain ferromagnetic dipolar couplings between clusters when they are highly nonspherical. Simple situations illustrate clearly this point.…”

“…12,14 For small values of the exchange splitting in the ferromagnetic material, those effects can be described in terms of the Ruderman-Kittel-Kasuya-Yosida ͑RKKY͒ theory. 13 However, in the presence of roughness at the interfaces, the dipolar interaction gives a nonzero contribution to the coupling, [17][18][19] which may be comparable to ͑or even larger than͒ the RKKY one. 19 On the basis of this result, we can expect the dipole interaction to play an important role in the case of granular materials.…”

Ferromagnetic resonance of a magnetic dimer with dipolar coupling

“…For this reason, many theoretical and experimental investigations are carried out towards a better control of this parameter and a better understanding of its effect on the magnetization dynamics in magnetic multilayers. In particular, the nature of this coupling is of special interest and its characterization is still a target of intense investigation 1,3,4,[9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24] . Depending on the intrinsic properties of the constituting layers (underlying material, thickness, roughness, energy parameters, etc.)…”

Strong lateral exchange coupling and current-induced switching in single-layer ferrimagnetic films with patterned compensation temperature

“…In spintronic architectures based on magnetic multilayers [1][2][3], interlayer couplings such as the Ruderman-Kittel-Kasuya-Yosida interaction [4,5], exchange coupling leading to exchange bias [6,7] and the dipolar interaction [8][9][10] allow for the tuning of the magnetic stability and electrical properties of the device [1][2][3]. The exchange interaction, composed of symmetric and antisymmetric parts, provides the strongest coupling channel in magnetic systems.…”