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arXiv · 0802.2539

Inelastic neutron scattering studies of Crystal Field Levels in PrOs$_4$As$_{12}$

Songxue Chi·Pengcheng Dai·T. Barnes·H. J. Kang·J. W. Lynn·R. Bewley·F. Ye·M. B. Maple·Z. Henkie·A. Pietraszko
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Abstract

We use neutron scattering to study the Pr$^{3+}$ crystalline electric field (CEF) excitations in the filled skutterudite PrOs$_4$As$_{12}$. By comparing the observed levels and their strengths under neutron excitation with the theoretical spectrum and neutron excitation intensities, we identify the Pr$^{3+}$ CEF levels, and show that the ground state is a magnetic $Γ_4^{(2)}$ triplet, and the excited states $Γ_1$, $Γ_4^{(1)}$ and $Γ_{23}$ are at 0.4, 13 and 23 meV, respectively. A comparison of the observed CEF levels in PrOs$_4$As$_{12}$ with the heavy fermion superconductor PrOs$_4$Sb$_{12}$ reveals the microscopic origin of the differences in the ground states of these two filled skutterudites.

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Songxue Chi, Pengcheng Dai, T. Barnes, H. J. Kang, J. W. Lynn, R. Bewley, F. Ye, M. B. Maple, Z. Henkie, A. Pietraszko. 2008-02-19. Inelastic neutron scattering studies of Crystal Field Levels in PrOs$_4$As$_{12}$. https://doi.org/10.1103/physrevb.77.094428

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