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arXiv · 0806.0767

External magnetic field effects on a distorted kagome antiferromagnet

J. -H. Kim·S. Ji·S. -H. Lee·B. Lake·T. Yildirim·H. Nojiri·K. Habicht·Y. Qiu·K. Kiefer
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Abstract

We report bulk magnetization, and elastic and inelastic neutron scattering measurements under an external magnetic field, $H$, on the weakly coupled distorted kagome system, Cu_{2}(OD)_3Cl. Our results show that the ordered state below 6.7 K is a canted antiferromagnet and consists of large antiferromagnetic $ac$-components and smaller ferromagnetic $b$-components. By first-principle calculations and linear spin wave analysis, we present a simple spin hamiltonian with non-uniform nearest neighbor exchange interactions resulting in a system of coupled spin trimers with a single-ion anisotropy that can qualitatively reproduce the spin dynamics of Cu_{2}(OD)_3Cl.

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J. -H. Kim, S. Ji, S. -H. Lee, B. Lake, T. Yildirim, H. Nojiri, K. Habicht, Y. Qiu, K. Kiefer. 2008-06-04. External magnetic field effects on a distorted kagome antiferromagnet. https://doi.org/10.1103/physrevlett.101.107201

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