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arXiv · 2002.05266

Topological magnonics in the two-dimensional van der Waals magnet CrI3

Esteban Aguilera·Rodrigo Jaeschke-Ubiergo·Nicolas Vidal-Silva·Luis Foa·Alvaro Núñez
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Abstract

In this article, we calculate the magnon spectrum of Kitaev-Heisenberg magnets. This model has been recently proposed as a spin Hamiltonian to model $\text{CrI}_3$ and other two-dimensional magnets. It is a minimal spin Hamiltonian that includes a contribution stemming from a Heisenberg, isotropic exchange, and a contribution arising from a Kitaev interaction, anisotropic and frustrated exchange. Our calculations reveal the topological nature of the magnons and a gap that opens at the $K$ and $K^\prime$ points. These topological properties give rise to effects such as thermal Hall effect. In addition to the bulk properties, we calculate the magnon spectrum of nanoribbons illustrating the corresponding edge states.

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Esteban Aguilera, Rodrigo Jaeschke-Ubiergo, Nicolas Vidal-Silva, Luis Foa, Alvaro Núñez. 2020-02-12. Topological magnonics in the two-dimensional van der Waals magnet CrI3. https://doi.org/10.1103/physrevb.102.024409

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