TY - JOUR
T1 - Neutron scattering study of the magnetic excitation spectra in mixed-valence 154Sm3Te4
AU - Alekseev, P. A.
AU - Mignot, J. M.
AU - Kahn, R.
AU - Ochiai, A.
AU - Clementyev, E. S.
AU - Lazukov, V. N.
AU - Nefeodova, E. V.
AU - Sadikov, I. P.
AU - Fabi, P.
PY - 2000/3/27
Y1 - 2000/3/27
N2 - The magnetic properties of the unconventional mixed-valence compound Sm3Te4 have been studied by inelastic neutron scattering. Time-of-flight experiments with different incident energies (Ei = 300 meV, 67 meV and 3.2 meV) and energy resolutions have been performed on isotopic (low-absorption) 154Sm3Te4 and on the reference compound La3Te4. Spectral contributions from two coexisting valence states Sm2+ and Sm3+ were clearly identified. In contrast to previous results for SmB6, the spectra can be analysed in terms of well defined 4f5 and 4f6 local moments subjected to the crystal field. However, the data reveal that di- and trivalent ions, which occupy identical crystallographic sites, feel quite different crystal-field potentials. Quasielastic scattering was found to exist down to the minimum temperature (1.5 K) of the measurements, with a half-width of about 0.45 meV. This implies that spin fluctuations, with a much higher fluctuation rate than the valence fluctuations reported in a recent NMR study, exist just above the spin-glass transition.
AB - The magnetic properties of the unconventional mixed-valence compound Sm3Te4 have been studied by inelastic neutron scattering. Time-of-flight experiments with different incident energies (Ei = 300 meV, 67 meV and 3.2 meV) and energy resolutions have been performed on isotopic (low-absorption) 154Sm3Te4 and on the reference compound La3Te4. Spectral contributions from two coexisting valence states Sm2+ and Sm3+ were clearly identified. In contrast to previous results for SmB6, the spectra can be analysed in terms of well defined 4f5 and 4f6 local moments subjected to the crystal field. However, the data reveal that di- and trivalent ions, which occupy identical crystallographic sites, feel quite different crystal-field potentials. Quasielastic scattering was found to exist down to the minimum temperature (1.5 K) of the measurements, with a half-width of about 0.45 meV. This implies that spin fluctuations, with a much higher fluctuation rate than the valence fluctuations reported in a recent NMR study, exist just above the spin-glass transition.
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U2 - 10.1088/0953-8984/12/12/312
DO - 10.1088/0953-8984/12/12/312
M3 - Article
AN - SCOPUS:24044461484
VL - 12
SP - 2725
EP - 2736
JO - Journal of Physics Condensed Matter
JF - Journal of Physics Condensed Matter
SN - 0953-8984
IS - 12
ER -