Published April 2006 | Version v1
Journal article

Evidence for unconventional superconducting fluctuations in heavy-fermion compound CeNi2Ge2

  • 1. Osaka Univ., Graduate School of Engineering Science, Toyonaka, Osaka (Japan)
  • 2. Okayama Univ., Faculty of Science, Okayama (JP)
  • 3. Toyama Prefectural Univ., Faculty of Engineering, Toyama (JP)
  • 4. Keio Univ., Dept. of Applied Physics and Physico-Informatics, Yokohama, Kanagawa (JP)
  • 5. Dept. of Materials Science and Engineering, Univ. of California at Berkeley, Berkely, CA (US)

Description

We present evidence for unconventional superconducting fluctuations in a heavy-fermion compound CeNi2Ge2. The temperature dependence of the 73Ge 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 Tconset=0.2 K and TcNQR=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. (author)

Additional details

Publishing Information

Journal Title
Journal of the Physical Society of Japan
Journal Volume
75
Journal Issue
4
Journal Page Range
p. 043702.1-043702.4
ISSN
0031-9015

Optional Information

Notes
18 ref., 5 figs.