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arXiv · 2210.15867

Stripe order and spin dynamics in triangular-lattice antiferromagnet KErSe$_{2}$: A single-crystal study with a theoretical description

Gaofeng Ding·Hongliang Wo·Rui Leonard Luo·Yimeng Gu·Yiqing Gu·Robert Bewley·Gang Chen·Jun Zhao
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Abstract

The rare-earth triangular-lattice chalcogenide is a great platform for exploring both spin liquids and novel magnetic orders with anisotropic spin interactions and magnetic frustrations. Here, we report the thermodynamic and neutron scattering measurements of rare-earth triangular-lattice chalcogenide KErSe$_{2}$, using single-crystal samples. Our experiments revealed a long-range stripe order below 0.2 K. Although the magnetic order was three-dimensional, magnetic excitations exhibited negligible modulation along the z direction, indicating very weak interlayer coupling. Furthermore, magnetic excitation developed a well-defined spin-wave dispersion with a gap of $\sim$0.03 meV at M points. Both the stripe order and spin-wave excitations could be quantitatively understood from the anisotropic spin interactions of the Er$^{3+}$ Kramers doublets.

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Gaofeng Ding, Hongliang Wo, Rui Leonard Luo, Yimeng Gu, Yiqing Gu, Robert Bewley, Gang Chen, Jun Zhao. 2022-10-28. Stripe order and spin dynamics in triangular-lattice antiferromagnet KErSe$_{2}$: A single-crystal study with a theoretical description. https://doi.org/10.1103/physrevb.107.l100411

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