Engineering domain structures in nanoscale magnetic thin films via strain

Wang

2015

Journal of Elec Materi

Using the molecular dynamics method based on the shell model, a uniaxially compressed single-crystal BaTiO 3 thin film with initial polarization configuration of double 90°domains has been simulated. Initiation and vertical propagation of domain switching induced by displacement loading lead to the occurrence of vortices and antivortices in pairs. However, further transverse extension results in separation between vortices and their corresponding antivortices of the same pair and the approach between vortices and antivortices of different pairs. As a result, a complete evolution process of the vortices and antivortices from initiation, to motion, then to collision, and finally to annihilation is observed. The internal mechanism of vortexantivortex pair evolution is revealed.

Section: Evolution Of Polarization Vortex Pairssupporting

confidence: 54%

Evolution of Polarization Vortex Pairs in a Uniaxially Compressed Single-Crystal BaTiO3 Thin Film: From Initiation to Annihilation

Tian

Wang

2015

Journal of Elec Materi

“…F ms , and F external are the magnetic exchange energy, magnetostatic energy, and external magnetic field energy, respectively, with the same formulations as in Ref. 33. The expression of elastic energy F elastic is the same as Eq.…”

mentioning

confidence: 99%

“…4 In doing so, both the partial relaxation of the initial structural strain during the magnetic thin film growth and the full transfer of electric-field-induced strain are incorporated. The heterogeneous strain e het , the volume average of which is zero, 33 is computed as…”

mentioning

confidence: 99%

On the elastically coupled magnetic and ferroelectric domains: A phase-field model

Applied Physics Letters

Nan

et al. 2014

Self Cite

Articles you may be interested inModeling of ferroelectric control of magnetic domain pattern and domain wall properties Fluctuation field and time dependence of magnetization in TbFeCo amorphous rare earth-transition metal thin films for perpendicular magnetic recording A phase-field model is developed to study local elastic coupling between magnetic and ferroelectric domains that show one-to-one pattern match. A multiferroic layered heterostructure of Co 0.4 Fe 0.6 /BaTiO 3 is considered as an example. Dynamics of the local elastic coupling is investigated by simulating a time-dependent electric-field driven changes in local magnetization/polarization/strain distributions and by comparing the associated velocities of the magnetic and ferroelectric domain walls. It is found that the electric-field-driven dynamic magnetic domain evolution manifests itself as an alternating occurrence of local magnetization rotation and coupled motion of magnetic and ferroelectric domain walls with almost identical velocities. V C 2014 AIP Publishing LLC. [http://dx.

“…In particular, the elastic energy E elas is calculated based on a previously developed phase-field model 40 for a threephase system that is comprised of an isolated magnetic nanoisland (the free layer herein), a stiff substrate, and the air. In this case, the stress-free boundary condition at the top and lateral surfaces of the magnetic nanoisland can be automatically incorporated by setting the elastic constants of the air phase as zero.…”

mentioning

confidence: 99%

Strain-assisted current-induced magnetization reversal in magnetic tunnel junctions: A micromagnetic study with phase-field microelasticity

Huang

Applied Physics Letters

et al. 2014

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Effect of substrate misfit strain on current-induced in-plane magnetization reversal in CoFeB-MgO based magnetic tunnel junctions is investigated by combining micromagnetic simulations with phase-field microelasticity theory. It is found that the critical current density for in-plane magnetization reversal decreases dramatically with an increasing substrate strain, since the effective elastic field can drag the magnetization to one of the four in-plane diagonal directions. A potential strainassisted multilevel bit spin transfer magnetization switching device using substrate misfit strain is also proposed. V