Analytical solution of the strain-controlled magnetic domain wall motion in bilayer piezoelectric/magnetostrictive nanostructures

Abstract

The one-dimensional propagation of magnetic domain walls in an isotropic, linearly elastic, magnetostrictive material is investigated in the framework of the extended Landau-Lifshitz-Gilbert equation where the effects of a spin-polarized current and a rate-independent dry-friction dissipation are taken into account. In our analysis, it is assumed that the ferromagnet is subject to a spatially uniform biaxial in-plain stress generated by a piezoelectric substrate combined with the former in a multiferroic heterostructure. Moreover, a possible connection between the dry-friction mechanism and the piezo-induced strains is conjectured. By adopting the traveling waves ansatz, the effect of such a stress on the domain wall dynamics is explored in both steady and precessional regimes. In particular, it is proved that the magnetoelastic contribution, while it does not formally modify the classical solution, affects both the propagation threshold and the Walker Breakdown conditions involved in the steady regime, in agreement with recent experimental results. In the precessional regime, it is shown that the existence of a correlation between the piezo-induced strains and dry-friction leads to an upward shift of the domain wall velocity.

Skyrmion motion induced by voltage-controlled in-plane strain gradients

“…To do so, we solve the Landau-Lifshitz-Gilbert equation 34 numerically. With exchange, magnetocrystalline anisotropy, magnetostatic, and interfacial DM contributions, we include a magnetoelastic field given by 35,36…”

Optimized Voltage-Induced Control of Magnetic Domain-Wall Propagation in Hybrid Piezoelectric/Magnetostrictive Devices

“…In our previous works [16][17][18], in particular, we carried out the mathematical modeling of the above-mentioned magnetization dynamics with particular emphasis on the characterization of the ME field felt by the MS layer as a function of the crystal symmetry (isotropic, cubic or hexagonal). The expressions of the physical quantities there provided were given in terms of the strains generated by the PZ layer, but such strains were left unidentified.…”

Tensor representation of magnetostriction for all crystal classes

“…All ferromagnetic materials exhibit a certain degree of magnetostriction and their capability of transforming magnetic energy into mechanical energy (and vice versa) makes them suitable for a large variety of micro-and nano-mechanical applications, ranging from sensors to actuators, from storage to information and communication technology devices. For instance, such materials have been successfully used in the design of hybrid piezoelectric-magnetostrictive structures with the goal of realizing a straincontrolled propagation of magnetic domain walls [9][10][11][12]. Analogously, spin dynamics controlled by magnetoelastic coupling and applied electric fields might play a significant role in the developments of future magnonic devices [13][14][15].…”