The antiferromagnet CeNiGe 3 exhibits superconductivity under pressure. The Néel temperature initially increases with increasing pressure up to 3 GPa and then becomes zero at a critical pressure (P C ) that is located at approximately 7 GPa. We found that superconductivity emerges from 1.7 GPa in the antiferromagnetic (AF) phase removed from P C . The superconductivity is realized in a wide pressure region including P C . The coefficient A in the resistivity and the upper critical field (H c2 ) significantly change against pressure. A feature of CeNiGe 3 is that the moderate heavy fermion state in the AF phase induces superconductivity.

We present evidence for unconventional superconducting fluctuations in a heavy-fermion compound CeNi2Ge2. The temperature dependence of the 73 Ge nuclear-spin-lattice-relaxation rate 1/T1 indicates the development of magnetic correlations and the formation of a Fermi-liquid state at temperatures lower than TFL = 0.4 K, where 1/T1T is constant. The resistance and 1/T1T measured on an as-grown sample decrease below T onset c = 0.2 K and T NQR c = 0.1 K, respectively; these are indicative of the onset of superconductivity. However, after annealing the sample to improve its quality, these superconducting signatures disappear. These results are consistent with the emergence of unconventional superconducting fluctuations in close proximity to a quantum critical point from the superconducting to the normal phase in CeNi2Ge2.

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kind of molecular properties of water: one is to disturb crystallization, while other is to promote crystallization. The competition between them can generate a pure amorphous state. Furthermore, lattice relaxation occurs around the boundary between crystal domains and the amorphous solid, since sharp Bragg peaks are observed at any phases.

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