2018/11/13 by H. B. Brentan, Brentan, H. B., Paulo F. Farinas +1
Physics and Astronomy · #FOS: Physical sciences #Magnetic properties of thin films #Physics of Superconductivity and Magnetism #Quantum and electron transport phenomena #Strongly Correlated Electrons (cond-mat.str-el)
paper · pdf · doi:10.48550/arxiv.1811.05380
openalex publication_date 2018/11/13 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Assuming a Fermi liquid behavior for s-conduction electrons, we rewrite the extended Landau-Lifshitz-Gilbert (LLG) equation renormalized by interactions through the Landau parameters Fal (l=0,1,2 ⋯) in an explicit form to describe the dynamic of a domain wall (DW) due to spin transfer torque phenomenon. The interaction between spins of the s-conduction electrons explains qualitatively the DW velocity experimental observations in \mathrmNi81\mathrmFe19 (Permalloy) recalculated by us without defects or impurity hypothesis. Close to Stoner ferromagnetic instability point where Fa0 ≈ -0.99, the DW velocity becomes high (v*DW≈ 600 ms-1) and critical spin current density becomes reduced (j*c≈1×1012 Am-2) when compared to that calculated by nonadiabatic approach. At the critical point, the DW velocity diverges while critical spin current density at the same point goes to zero. Our theory also provides a prediction to looking for materials in which is possible applies a smallest critical spin current density and observes higher DW velocity.