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Title: Vanishing RKKY interactions in Ce-based cage compounds
Abstract

We report the results of thermodynamic measurements in external magnetic field of the cubic Ce-based cage compounds CeT2Cd20(T= Ni,Pd). Our analysis of the heat-capacity data shows that the Γ7doublet is the ground state multiplet of the Ce3+ions. Consequently, for the Γ7doublet it can be theoretically shown that the Ruderman–Kittel–Kasuya–Yosida interaction between the localized Ce moments mediated by the conduction electrons, must vanish at temperatures much lower than the energy separating the ground state doublet from the first excited Γ8quartet. Our findings provide an insight as to why no long range order has been observed in these compounds down to temperatures in the milliKelvin range.

 
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Award ID(s):
1810310 1904315
NSF-PAR ID:
10446954
Author(s) / Creator(s):
; ; ; ; ; ; ;
Publisher / Repository:
IOP Publishing
Date Published:
Journal Name:
Journal of Physics: Condensed Matter
Volume:
35
Issue:
46
ISSN:
0953-8984
Page Range / eLocation ID:
Article No. 465601
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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