NMR investigation of a hole doped CeCoIn5

We have investigated the local environment of In and Co sites of the heavy fermion compound CeCo(In$_{1-x}$Cd$_{x}$)$_{5}$ ($x$ = 0.0, 0.10 and 0.15) using Nuclear Magnetic Resonance (NMR) and Nuclear Quadrupole Resonance (NQR) measurements. Recently, it was found that Cd-doping acts as an electronic tuning agent in CeCoIn$_{5}$ and that superconductivity (SC) and antiferromagnetism (AFM) coexist at ambient-pressure for $0.05 < x < 0.15$. It has also been observed on Cd doped compounds that pressure $P$ recovers the SC ground-state observed for the undoped compound suggesting it as a reversible tuning parameter. In this work we report data indicating that these phases indeed coexist microscopically. The NMR/NQR spectra of In and Co indicate the presence of electronic inhomogeneity, and the spin-lattice relaxation measurements $T_{1}^{-1}$ suggest that Cd doping induces changes to the low frequency spin dynamics only below $T \simeq 5 K$. Furthermore, $T_{1}^{-1}$ measurements for $x = 0.10$ under pressure show a different spin dynamics response in the paramagnetic state, in contrast with the effect of the chemical pressure. We show that chemical doping and pressure are not equivalent.