Vortex dynamics in Sr2RuO4 studied by O-17-NMR

We have measured O-17-nuclear spin-lattice relaxation rate T-1(-1) in the s uperconducting state of Sr2RuO4. A large enhancement of T-1(-1) was observe d in the mixed state, affected by the thermally enhanced fluctuation of vor tices. T-1 has two major components well below T-c: a shorter-T-1 component comes from the oxygen sites close to the vortices, whereas a longer-T-1 co mponent is from the sites far from the vortices. A peak of(T-1 T)(-1) appea rs when the thermal fluctuation rate tau(-1) become comparable to the NMR f requency. (C) 2000 Elsevier Science B.V. All rights reserved.