We report As75 nuclear magnetic resonance (NMR) and nuclear quadrupole resonance (NQR) studies on the superconductor Rb2Cr3As3 with a quasi-one-dimensional crystal structure. Below T∼100K, the spin-lattice relaxation rate (1/T1) divided by temperature, 1/T1T, increases upon cooling down to Tc=4.8K, showing a Curie-Weiss-like temperature dependence. The Knight shift also increases with decreasing temperature. These results suggest ferromagnetic spin fluctuation. In the superconducting state, 1/T1 decreases rapidly below Tc without a Hebel-Slichter peak, and follows a T5 variation below T∼3K, which points to unconventional superconductivity with point nodes in the gap function.
ASJC Scopus subject areas
- Physics and Astronomy(all)