Landau-Lifshitz-Bloch equation for domain wall motion in antiferromagnets

Chen, Z. Y.; Yan, Z. R.; Qin, Minghui; Liu, J.-M.

doi:10.1103/physrevb.99.214436

Cited by 10 publications

(6 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Using the values for J 1 to J 3 in Table I yields A(T = 0 K) = 2.34 × 10 −11 J/m, which agrees well with calculations of the exchange stiffness through atomistic simulations of the DW width, as shown in Fig. 10 We should emphasize here that we use a different equation for the exchange coupling to Chen et al [58]. They use an exchange term that sums over the opposite sublattice in the neighbouring macrospins.…”

Section: Domain Wall Motionsupporting

confidence: 79%

“…Additionally, the dynamics described by the LLB formalism for AFMs is incomplete. First attempts have been made to calculate the domain wall velocity due to a thermal gradient for a generic AFM using an LLB model [58]. However, the proposed model for AFM-LLB lacks a fundamental aspect of the magnetic properties at finite temperatures, the relaxation of the magnetization length.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Temperature-dependent micromagnetic model of the antiferromagnet Mn2Au : A multiscale approach

et al. 2022

View full text Add to dashboard Cite

Antiferromagnets (AFMs) are strong candidates for the future spintronic and memory applications largely because of their inherently fast dynamics and lack of stray fields, with Mn2Au being one of the most promising. For the numerical modelling of magnetic material properties, it is common to use ab-initio methods, atomistic models and micromagnetics. However, each method alone describes the physics within certain limits. Multiscale methods bridging the gap between these three approaches have been already proposed for ferromagnetic materials. Here, we present a complete multiscale model of the AFM Mn2Au as an exemplar material, starting with results from ab-initio methods going via atomistic spin dynamics (ASD) to an AFM Landau-Lifshitz-Bloch (AFM-LLB) model. Firstly, bulk Mn2Au is modelled using a classical spin Hamiltonian constructed based on earlier first-principles calculations. Secondly, this spin model is used in the stochastic Landau-Lifshitz-Gilbert (LLG) to calculate temperature-dependent equilibrium properties, such as magnetization and magnetic susceptibilities. Thirdly, the temperature dependent micromagnetic parameters are used in the AFM-LLB. We validate our approach by comparing the ASD and AFM-LLB models for three paradigmatic cases; (i) Damped magnetic oscillations, (ii) magnetization dynamics following a heat pulse resembling pump-probe experiments, (iii) magnetic domain wall motion under thermal gradients.

show abstract

Section: Domain Wall Motionsupporting

confidence: 79%

Section: Introductionmentioning

confidence: 99%

Temperature-dependent micromagnetic model of the antiferromagnet Mn2Au : A multiscale approach

et al. 2022

View full text Add to dashboard Cite

show abstract

“…By contrast, studies for bulk, intrinsic antiferromagnets still need to be reported. Theoretical analysis suggests that, in the absence of in-plane magnetic anisotropy or a Dzyaloshinskii-Moriya interaction (DMI), no preference is expressed for either Bloch or Néel walls [23][24][25][26][27]. The limited experimental knowledge about antiferromagnetic domain walls is due to a lack of techniques capable of spatially resolving the internal wall structure.…”

Section: Introductionmentioning

confidence: 99%

Coexistence of Bloch and Néel walls in a collinear antiferromagnet

et al. 2021

View full text Add to dashboard Cite

We resolve the domain-wall structure of the model antiferromagnet Cr 2 O 3 using nanoscale scanning diamond magnetometry and second-harmonic-generation microscopy. We find that the 180 • domain walls are predominantly Bloch-like, and can coexist with Néel walls in crystals with significant in-plane anisotropy. In the latter case, Néel walls that run perpendicular to a magnetic easy axis acquire a well-defined chirality. We further report quantitative measurement of the domain-wall width and surface magnetization. Our results provide fundamental input and an experimental methodology for the understanding of domain walls in pure, intrinsic antiferromagnets, which is relevant to achieve electrical control of domain-wall motion in antiferromagnetic compounds.

show abstract

“…Nowadays, the interest in antiferromagnets increases significantly due to the promising application potentials of the so-called antiferromagnetic (AFM) spintronics [1,2]. Comparing with ferromagnet based storage devices, AFM spintronic devices are more stable against magnetic field perturbations and could be designed with high element densities without producing a stray field, attributing to zero net magnetization and the ultralow susceptibility of AFM elements [3][4][5][6]. Moreover, AFM materials show fast magnetic dynamics [7], including ultrahigh frequency spin wave modes resulting from the complex spin configurations, and are highly favored for future devices [8].…”

Section: Introductionmentioning

confidence: 99%

Ultralow-loss domain wall motion driven by a magnetocrystalline anisotropy gradient in an antiferromagnetic nanowire

Wen

Chen

et al. 2020

Phys. Rev. Research

Self Cite

View full text Add to dashboard Cite

Searching for a new scheme to control the antiferromagnetic (AFM) domain wall is one of the most important issues for AFM spintronic devices. In this work, we study theoretically the domain wall motion of an AFM nanowire, driven by the axial anisotropy gradient generated by an external electric field and an electrocontrol of AFM domain wall motion in the merit of ultralow energy loss is demonstrated. The domain wall velocity depending on the anisotropy gradient magnitude and intrinsic material properties is simulated based on the Landau-Lifshitz-Gilbert equation and also deduced using the energy dissipation theorem. It is shown that the domain wall moves at a nearly constant speed for the small anisotropy gradient, and this motion is accelerated for the large gradient due to the enlarged domain wall width. While the domain wall mobility is independent of the lattice dimension and types of the domain wall, it can be enhanced by the Dzyaloshinskii-Moriya interaction. In addition, the physical mechanism for much faster AFM wall dynamics than ferromagnetic wall dynamics is qualitatively explained. This work unveils a promising strategy for controlling the AFM domain walls, benefiting the future of AFM spintronic applications.

show abstract

Landau-Lifshitz-Bloch equation for domain wall motion in antiferromagnets

Cited by 10 publications

References 46 publications

Temperature-dependent micromagnetic model of the antiferromagnet Mn2Au : A multiscale approach

Temperature-dependent micromagnetic model of the antiferromagnet Mn2Au : A multiscale approach

Coexistence of Bloch and Néel walls in a collinear antiferromagnet

Ultralow-loss domain wall motion driven by a magnetocrystalline anisotropy gradient in an antiferromagnetic nanowire

Contact Info

Product

Resources

About