Spin dynamics at oxygen sites in YBa2Cu3O7.
- Author(s): Hammel, PC;
- Takigawa, M;
- Heffner, RH;
- Fisk, Z;
- Ott, KC
- et al.
Published Web Locationhttps://doi.org/10.1103/physrevlett.63.1992
We report NMR measurements of the nuclear relaxation rate at all copper and oxygen sites in magnetically aligned powder samples of YBa2Cu3O7. Comparison of the oxygen and copper relaxation reveals a characteristic temperature greater than Tc. The copper relaxation rate is enhanced by antiferromagnetic copper spin fluctuations which are undiminished in the superconducting state. The absence of a coherence peak indicates that the superconductive pairing is not of the conventional BCS type. © 1989 The American Physical Society.