Ultrafast magnetization dynamics in half-metallic Co${}_2$FeAl Heusler alloy

Abstract

We report on optically induced, ultrafast magnetization dynamics in the Heusler alloy $\mathrm{C}{\mathrm{o}}_2\mathrm{FeAl}$, probed by time-resolved magneto-optical Kerr effect. Experimental results are compared to results from electronic structure theory and atomistic spin-dynamics simulations. Experimentally, we find that the demagnetization time (${\tau }_M$) in films of $\mathrm{C}{\mathrm{o}}_2\mathrm{FeAl}$ is almost independent of varying structural order, and that it is similar to that in elemental 3d ferromagnets. In contrast, the slower process of magnetization recovery, specified by ${\tau }_R$, is found to occur on picosecond time scales, and is demonstrated to correlate strongly with the Gilbert damping parameter ($\alpha$). Our results show that $\mathrm{C}{\mathrm{o}}_2\mathrm{FeAl}$ is unique, in that it is the first material that clearly demonstrates the importance of the damping parameter in the remagnetization process. Based on these results we argue that for $\mathrm{C}{\mathrm{o}}_2\mathrm{FeAl}$ the remagnetization process is dominated by magnon dynamics, something which might have general applicability.

References in corpus (19)

• Slater-Pauling Behavior of the Half-Ferromagnetic Full-Heusler Alloys
• Half-metallic ferromagnets: From band structure to many-body effects
• Calculated electronic and magnetic properties of the half-metallic, transition metal based Heusler compounds
• Super-Diffusive Spin-Transport as a Mechanism of Ultrafast Demagnetization
• A method for atomistic spin dynamics simulations: implementation and examples
• Ultrafast demagnetization of ferromagnetic transition metals: The role of the Coulomb interaction
• Ab-initio calculation of the Gilbert damping parameter via linear response formalism
• Spin-polarization and electronic properties of half-metallic Heusler alloys calculated from first-principles
• Spin-flip processes and ultrafast magnetization dynamics in Co - unifying the microscopic and macroscopic view of femtosecond magnetism
• Analysis of L21-ordering in full-Heusler Co2FeSi alloy thin films formed by rapid thermal annealing
• Calculating linear response functions for finite temperatures on the basis of the alloy analogy model
• The influence of photon angular momentum on ultrafast spin dynamics in Nickel
• Ultra-fast magnetisation rates within the Landau-Lifshitz-Bloch model
• Electron-phonon-scattering dynamics in ferromagnetic metals and its influence on ultrafast demagnetization processes
• Temperature-dependent Gilbert damping of Co2FeAl thin films with different degree of atomic order
• A microscopic model for ultrafast remagnetization dynamics
• Insights into ultrafast demagnetization in pseudo-gap half metals
• Magnetic and structural properties of Co2FeAl thin films grown on Si substrate
• Engineering of spin mixing conductance in Ru/FeCo/Ru interfaces: Effect of Re Doping

Cited by in corpus (3)

• Atomic disorder and Berry phase driven anomalous Hall effect in Co2FeAl Heusler compound
• Element resolved evidence of superdiffusive terahertz spin current arising from ultrafast demagnetization process
• Element selective ultrafast magnetization dynamics of hybrid Stoner-Heisenberg magnets