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Title: Superconductivity in Ce-based cage compounds
Abstract

Cerium-based ternary compounds CeNi2Cd20and CePd2Cd20do not exhibit long-range order down to millikelvin temperature range. Given the large separation between Ce ions which significantly reduces the super-exchange interactions and vanishingly small Ruderman–Kittel–Kasuya–Yosida interaction, here we show that nodal superconductivity mediated by the valence fluctuations must be a ground state in these materials. We propose that the critical temperature for the superconducting transition can be significantly increased by applying hydrostatic pressure. We employ an extended periodic Anderson lattice model which includes the long-range Coulomb interactions between the itinerant electrons as well as the local Coulomb interaction between the predominantly localized and itinerant electrons to compute a critical temperature of the superconducting transition. Using the slave-boson approach we show that fluctuations mediated by the repulsive electron–electron interactions lead to the emergence ofd-wave superconductivity.

 
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Award ID(s):
2002795
PAR ID:
10414391
Author(s) / Creator(s):
;
Publisher / Repository:
IOP Publishing
Date Published:
Journal Name:
Journal of Physics: Condensed Matter
Volume:
35
Issue:
33
ISSN:
0953-8984
Page Range / eLocation ID:
Article No. 335601
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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