Electron-phonon-scattering dynamics in ferromagnetic metals and its influence on ultrafast demagnetization processes

Abstract

We theoretically investigate spin-dependent carrier dynamics due to the electron-phonon interaction after ultrafast optical excitation in ferromagnetic metals. We calculate the electron-phonon matrix elements including the spin-orbit interaction in the electronic wave functions and the interaction potential. Using the matrix elements in Boltzmann scattering integrals, the momentum-resolved carrier distributions are obtained by solving their equation of motion numerically. We find that the optical excitation with realistic laser intensities alone leads to a negligible magnetization change, and that the demagnetization due to electron-phonon interaction is mostly due to hole scattering. Importantly, the calculated demagnetization quenching due to this Elliot-Yafet type depolarization mechanism is not large enough to explain the experimentally observed result. We argue that the ultrafast demagnetization of ferromagnets does not occur exclusively via an Elliott-Yafet type process, i.e., scattering in the presence of the spin-orbit interaction, but is influenced to a large degree by a dynamical change of the band structure, i.e., the exchange splitting.

References in corpus (4)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• Super-Diffusive Spin-Transport as a Mechanism of Ultrafast Demagnetization
• Ab initio investigation of Elliott-Yafet electron-phonon mechanism in laser-induced ultrafast demagnetization
• Influence of laser-excited electron distributions on the x-ray magnetic circular dichroism spectra: Implications for femtosecond demagnetization in Ni

Cited by in corpus (31)

• Ab initio theory of electron-phonon mediated ultrafast spin relaxation of laser-excited hot electrons in transition-metal ferromagnets
• Principles of spintronic THz emitters
• Ultrafast and Energy-Efficient Quenching of Spin Order: Antiferromagnetism Beats Ferromagnetism
• Role of critical spin fluctuations in ultrafast demagnetization of transition-metal rare-earth alloys
• Ultrafast demagnetization in bulk vs thin films: an ab-initio study
• Relativistic theory of spin relaxation mechanisms in the Landau-Lifshitz-Gilbert equation of spin dynamics
• Driving ferromagnets into a critical region of a magnetic phase diagram
• Interface reflectivity of a superdiffusive spin current in ultrafast demagnetization and THz emission
• Reexamination of the Elliott-Yafet spin-relaxation mechanism
• Insights into ultrafast demagnetization in pseudo-gap half metals
• Ab initio investigation of light-induced relativistic spin-flip effects in magneto-optics
• Ultrafast demagnetization in ferromagnetic materials: Origins and progress
• Ultrafast reduction of exchange splitting in ferromagnetic nickel
• Spin-orbit coupling effects on spin-dependent inelastic electronic lifetimes in ferromagnets
• Signatures of relativistic spin-light coupling in ultrafast magneto-optical pump-probe experiments
• Ultrafast magnetization dynamics in half-metallic Co${}_2$FeAl Heusler alloy
• Ultrafast magnetization reversal in ferromagnetic spin-valves: an s-d model perspective
• Ultrafast spin-lattice relaxation in ferromagnets including effective spin-orbit fields
• Accelerating the laser-induced demagnetization of a ferromagnetic film by antiferromagnetic order in an adjacent layer
• Laser-induced ultrafast transport and demagnetization at the earliest time: First-principles and real-time investigation
• Magnetic spin moment reduction in photoexcited ferromagnets through exchange interaction quenching: Beyond the rigid band approximation
• Electron-phonon scattering dynamics in ferromagnets on ultrafast timescales: Influence of the phonon temperature
• Generalized Elliott-Yafet spin-relaxation time for arbitrary spin mixing
• Ultrafast electron dynamics in altermagnetic materials
• Generation of Phonons with Angular Momentum During Ultrafast Demagnetization
• Spin Dependent Lifetimes and Spin-orbit Hybridization Points in Heusler Compounds
• Spin-phonon dispersion in magnetic materials
• Optically induced spin-dependent diffusive transport in the presence of spin-orbit interaction for all-optical magnetization reversal
• Interplay of electron-magnon scattering and spin-orbit induced electronic spin-flip scattering in a two-band Stoner model
• Optical signatures of bulk g-wave altermagnetism in MnTe
• Ultrafast electron-phonon scattering in antiferromagnetic Dirac semimetals