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Title: Renormalizations in unconventional superconducting states of Ce1-xYbxCoIn5
We have measured the superconducting penetration depth (T ) in the heavy-fermion/intermediate-valent superconducting alloy series Ce1−xYbxCoIn5 using a transverse-field muon spin relaxation to study the effect of intermediate-valent Yb doping on Fermi-liquid renormalization. From (T ) we determine the superfluid density ρs (T ) and find that it decreases continuously with increasing nominal Yb concentration x, i.e., with increasing intermediate valence. The temperature-dependent renormalization of the “normal” fluid density ρN (T ) = ρs (0) − ρs (T ) in both the heavy-fermion and intermediate valence limits is proportional to the temperature-dependent renormalization of the specific heat. This indicates that the temperature-dependent Fermiliquid Landau parameters of the superconducting quasiparticles entering the two different physical quantities are the same. These results represent an important advance in understanding of both intermediate valence and heavy-fermion phenomena in superconductors.  more » « less
Award ID(s):
1810310
PAR ID:
10105605
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Physical review. B, Condensed matter
Volume:
99
ISSN:
0163-1829
Page Range / eLocation ID:
035136
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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