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Precessional dynamics of elemental moments in a ferromagnetic alloy

W. E. Bailey·L. Cheng·D. Keavney·C. -C. Kao·E. Vescovo·D. Arena
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Abstract

We demonstrate an element-specific measurement of magnetization precession in a metallic ferromagnetic alloy, separating Ni and Fe moment motion in Ni81Fe19. Pump-probe X-ray magnetic circular dichroism (XMCD), synchronized with short magnetic field pulses, is used to measure free magnetization oscillations up to 2.6 GHz with elemental specificity and a rotational resolution of < 2 deg. Magnetic moments residing on Ni sites and Fe sites in a Ni81Fe19(50nm) thin film are found to precess together at all frequencies, coupled in phase within instrumental resolution of 90 ps.

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W. E. Bailey, L. Cheng, D. Keavney, C. -C. Kao, E. Vescovo, D. Arena. 2004-05-13. Precessional dynamics of elemental moments in a ferromagnetic alloy. https://doi.org/10.1103/physrevb.70.172403

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