Magnetic properties of Ce3+ in PbCeA (A= Te, Se, S)
American University of Beirut, Department of
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2 Instituto de Física, Universidade de São Paulo, 05315-970, São Paulo, Brazil
3 Laboratoire Charles Coulomb UMR 5221, Université Montpellier 2, Place Eugène Bataillon - CC069, F-34095 Montpellier Cedex 5 - France
4 Institute of Physics, Polish Academy of Sciences, Pl.02-668 Warsaw, Poland
The magnetic susceptibility of Pb1-xCexA (A = S, Se and Te) crystals with 0.006 ≤ x ≤ 0.036 were studied in the temperature range from 20 mK up to room temperature. X-band (~9.5 GHz) Electron Paramagnetic Resonance (EPR) showed small shifts in the effective Landé factors that were attributed to crystal-field admixture. The EPR measurements were correlated with the magnetic susceptibility data and resulted in estimating the crystal-field splitting Δ = E(Γ8) - E(Γ7) of the lowest 2F5/2 manifold for Ce3+ ions in PbA (A = S, Se and Te) of about 340 K, 440 K and 540 K for Pb1-xCexTe, Pb1-xCexSe, and Pb1-xCexS, respectively. The values for the crystal-field splitting deduced from the magnetic data were found to be in agreement with the calculated ones based on the point charge model. Moreover, the deHaas van-Alphen magnetic oscillations in the susceptibility measurements of Pb1-xCexTe (x~ 0.05 and 0.07) were observed at ultra-low temperature (20 mK); The oscillations were investigated and the values of the oscillatory period for Pb1-xCexTe (x = 0.0048 and 0.007) are reported.
© Owned by the authors, published by EDP Sciences, 2013