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Antiferromagnetic Domain Wall Motion Driven by Spin-Orbit Torques.

ABSTRACT: We theoretically investigate the dynamics of antiferromagnetic domain walls driven by spin-orbit torques in antiferromagnet-heavy-metal bilayers. We show that spin-orbit torques drive antiferromagnetic domain walls much faster than ferromagnetic domain walls. As the domain wall velocity approaches the maximum spin-wave group velocity, the domain wall undergoes Lorentz contraction and emits spin waves in the terahertz frequency range. The interplay between spin-orbit torques and the relativistic dynamics of antiferromagnetic domain walls leads to the efficient manipulation of antiferromagnetic spin textures and paves the way for the generation of high frequency signals from antiferromagnets.

SUBMITTER: Shiino T

PROVIDER: S-EPMC5101838 | biostudies-literature | 2016 Aug

REPOSITORIES: biostudies-literature

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Antiferromagnetic Domain Wall Motion Driven by Spin-Orbit Torques.

Shiino Takayuki T Oh Se-Hyeok SH Haney Paul M PM Lee Seo-Won SW Go Gyungchoon G Park Byong-Guk BG Lee Kyung-Jin KJ

Physical review letters 20160816 8

We theoretically investigate the dynamics of antiferromagnetic domain walls driven by spin-orbit torques in antiferromagnet-heavy-metal bilayers. We show that spin-orbit torques drive antiferromagnetic domain walls much faster than ferromagnetic domain walls. As the domain wall velocity approaches the maximum spin-wave group velocity, the domain wall undergoes Lorentz contraction and emits spin waves in the terahertz frequency range. The interplay between spin-orbit torques and the relativistic ...[more]

PMID: 27588878

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