Electronic inhomogeneity in a Kondo lattice

Bauer, E. D.*; Yang, Y.-F.*; Capan, C.*; Urbano, R. R.*; Miclea, C. F.*; Sakai, Hironori   ; Ronning, F.*; Graf, M. J.*; Balatsky, A. V.*; Movshovich, R.*; Bianchi, A. D.*; Reyes, A. P.*; Kuhns, P. L.*; Thompson, J. D.*; Fisk, Z.*

Here, we report a manifestation of electronic inhomogeneity in a strongly correlated -electron system, using CeCoIn as an example. A thermodynamic analysis of its superconductivity, combined with nuclear quadrupole resonance measurements, shows that nonmagnetic impurities (Y, La, Yb, Th, Hg, and Sn) locally suppress unconventional superconductivity, generating an inhomogeneous electronic "Swiss cheese" due to disrupted periodicity of the Kondo lattice. Our analysis may be generalized to include related systems, suggesting that electronic inhomogeneity should be considered broadly in Kondo lattice materials.