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arXiv · 1906.10326

Conductivity-Like Gilbert Damping due to Intraband Scattering in Epitaxial Iron

Behrouz Khodadadi·Anish Rai·Arjun Sapkota·Abhishek Srivastava·Bhuwan Nepal·Youngmin Lim·David A. Smith·Claudia Mewes·Sujan Budhathoki·Adam J. Hauser·Min Gao·Jie-Fang Li·Dwight D. Viehland·Zijian Jiang·Jean J. Heremans·Prasanna V. Balachandran·Tim Mewes·Satoru Emori
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Abstract

Confirming the origin of Gilbert damping by experiment has remained a challenge for many decades, even for simple ferromagnetic metals. In this Letter, we experimentally identify Gilbert damping that increases with decreasing electronic scattering in epitaxial thin films of pure Fe. This observation of conductivity-like damping, which cannot be accounted for by classical eddy current loss, is in excellent quantitative agreement with theoretical predictions of Gilbert damping due to intraband scattering. Our results resolve the longstanding question about a fundamental damping mechanism and offer hints for engineering low-loss magnetic metals for cryogenic spintronics and quantum devices.

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Behrouz Khodadadi, Anish Rai, Arjun Sapkota, Abhishek Srivastava, Bhuwan Nepal, Youngmin Lim, David A. Smith, Claudia Mewes, Sujan Budhathoki, Adam J. Hauser, Min Gao, Jie-Fang Li, Dwight D. Viehland, Zijian Jiang, Jean J. Heremans, Prasanna V. Balachandran, Tim Mewes, Satoru Emori. 2019-06-25. Conductivity-Like Gilbert Damping due to Intraband Scattering in Epitaxial Iron. https://doi.org/10.1103/physrevlett.124.157201

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