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arXiv · 0804.4437

Singlet-triplet dispersion reveals additional frustration in the triangular dimer compound Ba$_3$Mn$_2$O$_8$

M. B. Stone·M. D. Lumsden·S. Chang·E. C. Samulon·C. D. Batista·I. R. Fisher
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Abstract

We present single crystal inelastic neutron scattering measurements of the S=1 dimerized quasi-two-dimensional antiferromagnet Ba$_3$Mn$_2$O$_8$. The singlet-triplet dispersion reveals nearest-neighbor and next-nearest-neighbor ferromagnetic interactions between adjacent bilayers that compete against each other. Although the inter-bilayer exchange is comparable to the intra-bilayer exchange, this additional frustration reduces the effective coupling along the c-axis and leads to a quasi-two dimensional behavior. In addition, the obtained exchange values are able to reproduce the four critical fields in the phase diagram.

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M. B. Stone, M. D. Lumsden, S. Chang, E. C. Samulon, C. D. Batista, I. R. Fisher. 2008-04-28. Singlet-triplet dispersion reveals additional frustration in the triangular dimer compound Ba$_3$Mn$_2$O$_8$. https://doi.org/10.1103/physrevlett.100.237201

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