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arXiv · 2001.03175

Crystal field Hamiltonian and anisotropy in KErSe2 and CsErSe2

A. Scheie·V. O. Garlea·L. D. Sanjeewa·J. Xing·A. S. Sefat
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Abstract

We use neutron scattering and bulk property measurements to determine the single-ion crystal-field Hamiltonians of delafossites $\rm KErSe_2$ and $\rm CsErSe_2$. These two systems contains planar equilateral triangular Er lattices arranged in two stacking variants: rhombohedral (for K) or hexagonal (Cs). Our analysis shows that regardless the stacking order both compound exhibit an easy-plane ground state doublet with large $J_z=1/2$ terms and the potential for significant quantum effects, making them candidates for quantum spin liquid or other exotic ground states.

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A. Scheie, V. O. Garlea, L. D. Sanjeewa, J. Xing, A. S. Sefat. 2020-01-09. Crystal field Hamiltonian and anisotropy in KErSe2 and CsErSe2. https://doi.org/10.1103/physrevb.101.144432

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