| 1. |
- Borlenghi, Simone, et al.
(författare)
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Energy and magnetization transport in nonequilibrium macrospin systems
- 2015
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Ingår i: Physical Review E. Statistical, Nonlinear, and Soft Matter Physics. - 1539-3755 .- 1550-2376. ; 92:1
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Tidskriftsartikel (refereegranskat)abstract
- We investigate numerically the magnetization dynamics of an array of nanodisks interacting through the magnetodipolar coupling. In the presence of a temperature gradient, the chain reaches a nonequilibrium steady state where energy and magnetization currents propagate. This effect can be described as the flow of energy and particle currents in an off-equilibrium discrete nonlinear Schrodinger (DNLS) equation. This model makes transparent the transport properties of the system and allows for a precise definition of temperature and chemical potential for a precessing spin. The present study proposes a setup for the spin-Seebeck effect, and shows that its qualitative features can be captured by a general oscillator-chain model.
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| 2. |
- Chimata, Raghuveer, et al.
(författare)
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Laser heated ferromagnetic simulations
- 2015
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Ingår i: ULTRAFAST MAGNETISM I. - Cham : Springer International Publishing. - 9783319077437 - 9783319077420 ; , s. 76-78
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Konferensbidrag (refereegranskat)abstract
- In this work, we show a model of ferromagnetic material heated by a laser pulse. The laser creates a pattern of circles on the ferromagnetic materials with hot regions heated up to 3000K and cold regions at 100K and 400K. In our model the Landau-Lifshitz-Gilbert equation for a macrospin and spin temperature is passed through stochastic field. We show that the difference of magnon dispersion in the cold regions of the material.
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| 3. |
- Dürrenfeld, Philipp, et al.
(författare)
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Tunable damping, saturation magnetization, and exchange stiffness of half-Heusler NiMnSb thin films
- 2015
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Ingår i: Physical Review B. - : American Physical Society. - 1098-0121 .- 1550-235X. ; 92:21
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Tidskriftsartikel (refereegranskat)abstract
- The half-metallic half-Heusler alloy NiMnSb is a promising candidate for applications in spintronic devices due to its low magnetic damping and its rich anisotropies. Here we use ferromagnetic resonance (FMR) measurements and calculations from first principles to investigate how the composition of the epitaxially grown NiMnSb influences the magnetodynamic properties of saturation magnetization M-S, Gilbert damping alpha, and exchange stiffness A. M-S and A are shown to have a maximum for stoichiometric composition, while the Gilbert damping is minimum. We find excellent quantitative agreement between theory and experiment for M-S and alpha. The calculated A shows the same trend as the experimental data but has a larger magnitude. In addition to the unique in-plane anisotropy of the material, these tunabilities of the magnetodynamic properties can be taken advantage of when employing NiMnSb films in magnonic devices.
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| 4. |
- Nystrand, Thomas, et al.
(författare)
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Coarse-Graining Approach to Atomistic SpinDynamics
- 2015
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Ingår i: ULTRAFAST MAGNETISM I. - Cham : Springer International Publishing. - 9783319077437 - 9783319077420 ; , s. 162-165
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Konferensbidrag (refereegranskat)abstract
- We introduce a coarse-graining approach to study the movement of a Domain Wall (DW) under the influence of a spin polarized current, in the framework of atomistic spin dynamics. An increase in performance of up to 35% is obtained. We show the dependence of the method on both exchange range and temperature effects.
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