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arXiv · 1904.11779

Homogenous reduced moment in a gapful scalar chiral kagome antiferromagnet

A. Scheie·S. Dasgupta·M. Sanders·A. Sakai·Y. Matsumoto·T. R. Prisk·S. Nakatsuji·R. J. Cava·C. Broholm
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Abstract

We present present a quantitative experimental investigation of the scalar chiral magnetic order with in $\rm{Nd_3Sb_3Mg_2O_{14}}$. Static magnetization reveals a net ferromagnetic ground state, and inelastic neutron scattering from the hyperfine coupled nuclear spin reveals a local ordered moment of 1.76(6) $\mu_B$, just 61(2)% of the saturated moment size. The experiments exclude static disorder as the source of the reduced moment. A 38(1) $\mu$eV gap in the magnetic excitation spectrum inferred from heat capacity rules out thermal fluctuations and suggests a multipolar explanation for the moment reduction. We compare $\rm{Nd_3Sb_3Mg_2O_{14}}$ to Nd pyrochlores and show that it is close to a moment fragmented state.

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A. Scheie, S. Dasgupta, M. Sanders, A. Sakai, Y. Matsumoto, T. R. Prisk, S. Nakatsuji, R. J. Cava, C. Broholm. 2019-04-26. Homogenous reduced moment in a gapful scalar chiral kagome antiferromagnet. https://doi.org/10.1103/physrevb.100.024414

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