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arXiv · 2001.06217

Fermi Level Controlled Ultrafast Demagnetization Mechanism in Half-Metallic Heusler Alloy

Santanu Pan·Takeshi Seki·Koki Takanashi·Anjan Barman
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Abstract

The electronic band structure-controlled ultrafast demagnetization mechanism in Co2FexMn1-xSi Heusler alloy is underpinned by systematic variation of composition. We find the spin-flip scattering rate controlled by spin density of states at Fermi level is responsible for non-monotonic variation of ultrafast demagnetization time ({\tau}M) with x with a maximum at x = 0.4. Furthermore, Gilbert damping constant exhibits an inverse relationship with {\tau}M due to the dominance of inter-band scattering mechanism. This establishes a unified mechanism of ultrafast spin dynamics based on Fermi level position.

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Santanu Pan, Takeshi Seki, Koki Takanashi, Anjan Barman. 2020-01-17. Fermi Level Controlled Ultrafast Demagnetization Mechanism in Half-Metallic Heusler Alloy. https://doi.org/10.1103/physrevb.101.224412

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