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arXiv · 1106.0161

Ferromagnetic and antiferromagnetic dimer splittings in LaMn0.1Ga0.9O3

A. Furrer·E. Pomjakushina·V. Pomjakushin·J. P. Embs·Th. Straessle
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Abstract

Inelastic neutron scattering was employed to study the magnetic excitations of Mn3+ dimers in LaMn0.1Ga0.9O3. The nearest-neighbor interaction of Mn3+ ions is ferromagnetic in the basal (a,b)-plane, but antiferromagnetic along the c-direction, thus two different types of dimer excitations are simultaneously present in the experiments. From the observed energy spectra we derive Heisenberg-type exchange interactions Jab=0.210(4) meV and Jc=-0.285(5) meV as well as an axial anisotropy parameter D=0.036(6) meV. These parameters considerably differ from those derived for the isostructural parent compound LaMnO3 due to structural effects.

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A. Furrer, E. Pomjakushina, V. Pomjakushin, J. P. Embs, Th. Straessle. 2011-06-01. Ferromagnetic and antiferromagnetic dimer splittings in LaMn0.1Ga0.9O3. https://doi.org/10.1103/physrevb.83.174442

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