Spin-wave dynamics in the KCeS2 delafossite: A theoretical description of powder inelastic neutron-scattering data

Abstract

Layered rare-earth delafossites $AR{X}_2$ with $R$ = Yb(III) or Ce(III) have received a lot of interest as potential hosts for a quantum spin-liquid ground state. Some systems of this family that show no long-range order down to the lowest measured temperatures, such as NaYbO${}_2$, NaYbS${}_2$, and NaYbSe${}_2$, are presumed to be in a quantum spin-liquid state. However, other isostructural compounds are known to order antiferromagnetically at subkelvin temperatures. Among them, KCeS${}_2$ exhibits stripe-$yz$ magnetic order in the triangular-lattice planes that sets in below 400 mK. Here we investigate the spin-wave spectrum of this ordered phase with powder inelastic neutron scattering and describe it using a model Hamiltonian obtained from first-principles calculations based on the complete $|J,m_J⟩$ multiplet description of the Ce sites with an anisotropic nearest-neighbor exchange interaction. Combing the current understanding of the exchange interaction in the systems with the effects of texturing in the powder, we have been able to model the inelastic neutron scattering spectrum with high fidelity.

6 pages, 3 figures, accepted to Phys. Rev. B

References in corpus (12)

• Scattering Continuum and Possible Fractionalized Excitations in $\alpha$-RuCl${}_3$
• Hyper-honeycomb iridate $\beta$-Li2IrO3 as a platform for Kitaev magnetism
• Anisotropic field-induced ordering in the triangular-lattice quantum spin liquid NaYbSe${}_2$
• Field-induced instability of the quantum-spin-liquid ground state in the $J_{\mathrm{eff}}=\frac{1}{2}$ triangular-lattice compound NaYbO${}_2$
• Theory of the field-revealed Kitaev spin liquid
• Quantum spin liquid ground state in the disorder free triangular lattice NaYbS${}_2$
• Field-induced magnetic transition and spin fluctuation in quantum spin liquid candidate CsYbSe${}_2$
• Spin excitations in the frustrated triangular lattice antiferromagnet NaYbO${}_2$
• Exchange interaction between $J$-multiplets
• Confinement-Deconfinement Transition as an Indication of Spin-Liquid-Type Behavior in Na${}_2$IrO${}_3$
• Long-range magnetic order in the $\tilde{S}=1/2$ triangular lattice antiferromagnet KCeS${}_2$
• Stripe-yz magnetic order in the triangular-lattice antiferromagnet KCeS2

Cited by in corpus (7)

• Quantum Spin Dynamics Due to Strong Kitaev Interactions in the Triangular-Lattice Antiferromagnet CsCeSe${}_2$
• Rare-Earth Chalcogenides: An Inspiring Playground For Exploring Frustrated Magnetism
• Exchange renormalized crystal field excitation in a quantum Ising magnet KTmSe${}_2$
• Stripe order and spin dynamics in triangular-lattice antiferromagnet KErSe${}_2$: A single-crystal study with a theoretical description
• Dominant Kitaev interaction and field-induced quantum phase transitions in triangular-lattice KCeSe2
• Spin Liquid Mimicry in the Hydroxide Double Perovskite CuSn(OH)${}_6$ Induced by Correlated Proton Disorder
• 5d-mediated indirect exchange and effective spin Hamiltonians in Ce triangular-lattice delafossites