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arXiv · 1104.2558

Spin dynamics in the S =1/2 kagome compound vesignieite, Cu3Ba(VO5H)2

Ross H Colman·Fabrice Bert·David Boldrin·Adrian D Hillier·Laurent C Chapon·Pascal Manuel·Phillipe Mendels·Andrew S Wills
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Abstract

We report the study of high quality samples of the frustrated S = 1/2 kagome antiferromagnet vesignieite, Cu3Ba(VO5H)2. Neutron powder diffraction measurements evidence the high quality of the kagome lattice and show no sign of a transition to long-range order. A kink in the susceptibility below T = 9 K is matched to a reduction in paramagnetic-like correlations in the diffraction data and a slowing of the spin dynamics observed by MuSR. Our results point to an exotic quantum state below 9 K with coexistance of both dynamical and small frozen moments \sim 0.1 \muB. We propose that Dzyaloshinsky-Moriya interaction is large enough in this system to stabilize this novel quantum ground state.

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Ross H Colman, Fabrice Bert, David Boldrin, Adrian D Hillier, Laurent C Chapon, Pascal Manuel, Phillipe Mendels, Andrew S Wills. 2011-04-13. Spin dynamics in the S =1/2 kagome compound vesignieite, Cu3Ba(VO5H)2. https://doi.org/10.1103/physrevb.83.180416

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