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This content will become publicly available on March 1, 2023

Title: Crystal-field excitations and quadrupolar fluctuations of 4f-electron systems studied by polarized light scattering
Abstract We present Raman-scattering results for three materials, CeB 6 , TbInO 3 , and YbRu 2 Ge 2 , to illustrate the essential aspects of crystal-field (CF) excitations and quadrupolar fluctuations of 4 f -electron systems. For CF excitations, we illustrate how the 4 f orbits are split by spin-orbit coupling and CF potential by presenting spectra for inter- and intra-multiplet excitations over a large energy range. We discuss identification of the CF ground state and establishment of low-energy CF level scheme from the symmetry and energy of measured CF excitations. In addition, we demonstrate that the CF linewidth is a sensitive probe of electron correlation by virtue of self-energy effect. For quadrupolar fluctuations, we discuss both ferroquadrupolar (FQ) and antiferroquadrupolar (AFQ) cases. Long-wavelength quadrupolar fluctuations of the same symmetry as the FQ order parameter persists well above the transition temperature, from which the strength of electronic intersite quadrupolar interaction can be evaluated. The tendency towards AFQ ordering induces ferromagnetic correlation between neighboring 4 f -ion sites, leading to long-wavelength magnetic fluctuations.
Authors:
; ; ; ; ; ; ; ; ; ;
Award ID(s):
1709161 2105001
Publication Date:
NSF-PAR ID:
10324119
Journal Name:
Journal of Physics: Conference Series
Volume:
2164
Issue:
1
Page Range or eLocation-ID:
012054
ISSN:
1742-6588
Sponsoring Org:
National Science Foundation
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