We report the 115In nuclear spin-lattice relaxation rate (1/T1) measurements down to 90 mK in the new heavy fermion (HF) compound Celrln 5. At 0.4 K ≤ T ≤ 100 K, 1/T1 is strongly T-dependent, which indicates that the 4f electrons are much more itinerant than in known Ce- based HFs. From the unique temperature variation of 1/T1T, we find that this compound is located near a quantum critical point, with anisotropic spin fluctuations due to a layered crystal structure. Below the bulk superconductivity temperature 0.40 K, 1/T1 follows a T3 variation without a coherence peak, which indicates unconventional superconductivity with line-node gap. These aspects are reminiscent of the high-Tc copper oxides and suggest the importance of the magnetic fluctuations for the occurrence of the unconventional superconductivity.
ASJC Scopus subject areas
- Physics and Astronomy(all)