Crystal-field Hamiltonian and anisotropy in <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mi>KErSe</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:math> and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mi>CsErSe</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:math>
Allen Scheie, V. Ovidiu Garlea, Liurukara D. Sanjeewa, Jie Xing, Athena S. Sefat
Abstract
We use neutron scattering and bulk property measurements to determine the single-ion crystal-field Hamiltonians of delafossites ${\mathrm{KErSe}}_{2}$ and ${\mathrm{CsErSe}}_{2}$. These two systems contain planar equilateral triangular Er lattices arranged in two stacking variants: rhombohedral (for K) or hexagonal (Cs). Our analysis shows that regardless of the stacking order both compounds 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.
Topics & Concepts
Equilateral triangleCrystallographyPhysicsAnisotropyHamiltonian (control theory)Crystal (programming language)Condensed matter physicsChemistryGeometryQuantum mechanicsComputer scienceMathematicsMathematical optimizationProgramming languageAdvanced Condensed Matter PhysicsMagnetic and transport properties of perovskites and related materialsMultiferroics and related materials