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arXiv · 1310.7317

Magnetic structure and spin excitations in BaMn2Bi2

S. Calder·B. Saparov·H. B. Cao·J. L. Niedziela·M. D. Lumsden·A. S. Sefat·A. D. Christianson
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Abstract

We present a single crystal neutron scattering study of BaMn2Bi2, a recently synthesized material with the same ThCr2Si2-type structure found in several Fe-based unconventional superconducting materials. We show long range magnetic order, in the form of a G-type antiferromagnetic structure, to exist up to 390 K with an indication of a structural transition at 100 K. Utilizing inelastic neutron scattering we observe a spin-gap of 16meV, with spin-waves extending up to 55 meV. We find these magnetic excitations to be well fit to a J1-J2-Jc Heisenberg model and present values for the exchange interactions. The spin wave spectrum appears to be unchanged by the 100 K structural phase transition.

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S. Calder, B. Saparov, H. B. Cao, J. L. Niedziela, M. D. Lumsden, A. S. Sefat, A. D. Christianson. 2013-10-28. Magnetic structure and spin excitations in BaMn2Bi2. https://doi.org/10.1103/physrevb.89.064417

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