Theory of laser-induced demagnetization at high temperatures
TLDR
In this article, a self-consistent random phase approximation of the spin system was derived for a broad range of temperature and the dependence of demagnetization on the temperature and pumping laser intensity was calculated in detail.Abstract:
Laser-induced demagnetization is theoretically studied by explicitly taking into account interactions among electrons, spins, and lattice. Assuming that the demagnetization processes take place during the thermalization of the subsystems, the temperature dynamics is given by the energy transfer between the thermalized interacting baths. These energy transfers are accounted for explicitly through electron-magnon and electron-phonon interactions, which govern the demagnetization time scale. By properly treating the spin system in a self-consistent random phase approximation, we derive magnetization dynamic equations for a broad range of temperature. The dependence of demagnetization on the temperature and pumping laser intensity is calculated in detail. In particular, we show several salient features for understanding magnetization dynamics near the Curie temperature. While the critical slowdown in dynamics occurs, we find that an external magnetic field can restore the fast dynamics. We discuss the implication of the fast dynamics in the application of heat-assisted magnetic recording.read more
Citations
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Perspective: Ultrafast magnetism and THz spintronics
Jakob Walowski,Markus Münzenberg +1 more
TL;DR: In this article, the authors review the need for multiscale modeling to address the processes starting from electronic excitation of the spin system on the picometer length scale and sub-femtosecond time scale, to spin wave generation, and towards the modeling of ultrafast phase transitions that altogether determine the response time of the ferromagnetic system.
Journal ArticleDOI
Perspective: Ultrafast magnetism and THz spintronics
Jakob Walowski,Markus Münzenberg +1 more
TL;DR: In this article, the authors review the need for multiscale modeling to address processes starting from electronic excitation of the spin system on the picometer length scale and sub-femtosecond time scale, and towards the modeling of ultrafast phase transitions that altogether determine the response time of the ferromagnetic system.
Journal ArticleDOI
Spin current generated by thermally driven ultrafast demagnetization
TL;DR: Thermally driven ultrafast demagnetization of a perpendicular ferromagnet leads to spin accumulation in a normal metal and spin transfer torque in an in-plane ferromaagnet.
Journal ArticleDOI
Thermal spin-transfer torque driven by the spin-dependent Seebeck effect in metallic spin-valves
Gyung-Min Choi,Gyung-Min Choi,Chul Hyun Moon,Chul Hyun Moon,Byoung-Chul Min,Kyung Jin Lee,David G. Cahill +6 more
TL;DR: The spin-dependent Seebeck effect converts thermal gradients into spin currents as mentioned in this paper, which can be used to drive spin transfer torques on picosecond timescales using the heat currents created by ultrafast pulses of laser light.
Journal ArticleDOI
The Ultrafast Laser Pump-Probe Technique for Thermal Characterization of Materials With Micro/Nanostructures
TL;DR: In this article, the state-of-the-art ultrafast pump-probe method applied to study the thermal and magnetic properties of materials at the micro and nanometer scales is reviewed.
References
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Journal ArticleDOI
Ultrafast spin-dynamics in half-metallic Cr O 2 thin films
TL;DR: In this article, an extended three-temperature model (3TM) was proposed to study the spin dynamics in epitaxial ultradensemble film, and different microscopic contributions leading to incoherent spin thermalization and relaxation on distinct time scales have been identified in an extended 3TM model.
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Specific heat contributions of the ferromagnetic transition in nickel and nickel-copper alloys☆
R.E. Pawel,E.E. Stansbury +1 more
TL;DR: In this paper, the specific heat contribution due to magnetic order in pure nickel was determined by subtracting the theoretical specific heat, computed on the basis of no magnetic effects, from recently determined experimental values.
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Theory for the dynamics of excited electrons in noble and transition metals
TL;DR: In this article, the role of secondary electrons, transport and electron-phonon collisions in the hot-electron distribution, the two-photon photoemission (2PPE) current and the relaxation time and compare them to experimental data for noble and transition metals.
Journal ArticleDOI
Time-resolved and energy-dispersed spin excitation in ferromagnets and clusters under influence of femtosecond laser pulses
TL;DR: In this article, the energy dispersion of the spin-moment change in ferromagnetic Ni and the effect of the distance between the magnetic centers upon the spin localization and local spin-flip times in metallic chains are investigated.