Evolution of the superconducting energy gap structure concomitant with Fermi surface reconstruction in the heavy-fermion superconductor CeCoIn5

Hyunsoo Kim, M. A. Tanatar, R. Flint +6

The London penetration depth, $\lambda (T)$ was measured in single crystals of Ce${}_{1-x}{R}_x$CoIn${}_5$, $R$=La, Nd and Yb down to 50~mK ($T_c/T\sim$50) using a tunnel-diode resonator. In t…