The many faces of quantum kagome materials: Interplay of further-neighbour exchange and Dzyaloshinskii-Moriya interaction

Tsezar F. Seman; Cheng-Chien Chen; Rajiv R. P. Singh; Michel van Veenendaal

paper

The many faces of quantum kagome materials: Interplay of further-neighbour exchange and Dzyaloshinskii-Moriya interaction

arXiv:1508.01523

Abstract

The field of frustrated magnetism has been enriched significantly by the discovery of various kagome lattice compounds. These materials exhibit a great variety of macroscopic behaviours ranging from magnetic orders to quantum spin liquids. Using large-scale exact diagonalization, we construct the phase diagram of the $S = 1/2$ $J_{1}$ - $J_{2}$ kagome Heisenberg model with $z$ -axis Dzyaloshinskii-Moriya interaction $D_{z}$ . We show that this model can systematically account for many of the experimentally observed phases. Small $J_{2}$ and $D_{z}$ can stabilize respectively a gapped and a gapless spin liquid. When $J_{2}$ or $D_{z}$ is substantial, the ground state develops a $Q = 0$ , $12 0^{o}$ antiferromagnetic order. The critical strengths for inducing magnetic transition are $D_{z}^{c} \sim 0.1 J_{1}$ at $J_{2} = 0$ , and $J_{2}^{c} \sim 0.4 J_{1}$ at $D_{z} = 0$ . The previously reported values of $D_{z}$ and $J_{2}$ for herbertsmithite [ZnCu $_{3}$ (OH) $_{6}$ Cl $_{2}$ ] place the compound in close proximity to a quantum critical point.

arXiv comment6+1 pages, 3+1 figures, including supplemental material

Cited by in corpus (1)

High-Field Expansion Approach to Kagome Antiferromagnets with Dzyaloshinskii-Moriya Interactions