Vibronic and magnetic excitations in the spin-orbital liquid state of FeSc2S4.
Inelastic neutron scattering results on the spin-orbital liquid in FeSc2S4 are presented. This sulfospinel reveals strong geometric frustration in the spin and in the orbital sector. In the present experiments the orbital liquid is evidenced by a clear spectroscopic signature of a dynamic Jahn-Teller effect with a vibronic splitting 3Gamma approximately 2 meV in agreement with theoretical estimates. The excitations of the spin liquid reveal strong dispersion and can be characterized as cooperative spin excitations in a supercooled paramagnet with a spin gap of Delta approximately 0.2 meV.
Krimmel
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Experimentalphysik V, Center for Electronic Correlations and Magnetism, Universität Augsburg, D-86159 Augsburg, Germany.
Mücksch
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Tsurkan
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V
Koza
M M
MM
Mutka
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H
Loidl
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