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Abstract: We present an In(1) NQR study on the heavy-fermion (HF) compound CeCo(In1−x Cd x )5 . Bulk measurements indicate that Cd doping acts as an electronic tuning agent in CeCoIn5, and that superconductivity (SC) and antiferromagnetism (AFM) may coexist at ambient pressure for . For , the nuclear spin lattice relaxation rate shows a broad peak at the Néel temperature , with a subsequent onset of SC at . Our results provide strong evidence for microscopic coexistence of these two ground states. The nuclear magnetization recovery curves in both the ordered and mixed states reveal a single -component, which suggests a homogeneous nature of the Ce-4f1 electronic state. [Copyright &y& Elsevier]

Abstract: We show that the NMR Knight shift anomaly exhibited by a large number of heavy electron materials can be understood in terms of the different hyperfine couplings of probe nuclei to localized spins and to conduction electrons. The onset of the anomaly is at a temperature , below which an itinerant component of the magnetic susceptibility develops. This second component characterizes the polarization of the conduction electrons by the local moments and is a signature of the emerging heavy electron state. The heavy electron component grows as below , and scales universally for all measured Ce, Yb and U based materials. Our results suggest that is not related to the single-ion Kondo temperature, , but rather represents a correlated Kondo temperature that provides a measure of the strength of the intersite coupling between the local moments. [Copyright &y& Elsevier]

Abstract: The heavy fermion system exhibits antiferromagnetism for both and . is antiferromagnetic at ambient pressure and superconducting under hydrostatic pressure, whereas is superconducting at ambient pressure, but becomes antiferromagnetic with substitution of In by a few percent of Cd. Pure exhibits a field-induced magnetic phase that coexists with the superconductivity. Nuclear magnetic resonance (NMR) and nuclear quadrupolar resonance (NQR) studies of the In(1), In(2) and Co sites reveal similar features in the magnetic states of these systems. [Copyright &y& Elsevier]