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arXiv · 1611.01512

Magnonic analog of relativistic Zitterbewegung in an antiferromagnetic spin chain

Weiwei Wang·Chenjie Gu·Yan Zhou·Hans Fangohr
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Abstract

We theoretically investigate the spin wave (magnon) excitations in a classical antiferromagnetic spin chain with easy-axis anisotropy. We obtain a Dirac-like equation by linearizing the Landau- Lifshitz-Gilbert equation in this antiferromagnetic system, in contrast to the ferromagnetic system in which a Schr\"{o}dinger equation is derived. The Hamiltonian operator in the Dirac-like equation is a pseudo-Hermitian. We compute and demonstrate the relativistic Zitterbewegung (trembling motion) in the antiferromagnetic spin chain by measuring the expectation values of the wave packet position.

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Weiwei Wang, Chenjie Gu, Yan Zhou, Hans Fangohr. 2016-11-05. Magnonic analog of relativistic Zitterbewegung in an antiferromagnetic spin chain. https://doi.org/10.1103/physrevb.96.024430

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