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Collective magnetic excitations in mixed-valence Sm0.83Y0.17S

P. A. Alekseev·J. -M. Mignot·A. Ochiai·E. V. Nefeodova·I. P. Sadikov·E. S. Clementyev·V. N. Lazukov·M. Braden·K. S. Nemkovski
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Abstract

The magnetic spectral response of black-phase mixed-valence Sm0.83Y0.17S has been measured by inelastic neutron scattering on a single crystal. Two magnetic peaks are observed in the energy range of the Sm2+ spin-orbit transition (25-40 meV). Both of them exhibit significant dispersion along the three main symmetry directions, reminiscent of the spin-orbit exciton branch found in pure divalent SmS. The results can be reproduced by a simple phenomenological model accounting for the existence of sizeable Sm-Sm exchange interactions, and a microscopic mechanism is proposed on the basis of the "local-bound-state" theory developed previously for SmB6.

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P. A. Alekseev, J. -M. Mignot, A. Ochiai, E. V. Nefeodova, I. P. Sadikov, E. S. Clementyev, V. N. Lazukov, M. Braden, K. S. Nemkovski. 2001-12-18. Collective magnetic excitations in mixed-valence Sm0.83Y0.17S. https://doi.org/10.1103/physrevb.65.153201

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