Effect of vortex fluctuations onTl205spin-lattice relaxation in the mixed state ofTl2Ba2CuO6

Abstract
The spin-lattice relaxation rate W on Tl205 has been measured in the mixed state of a Tl2 Ba2 CuO6 aligned powder sample with Tc=100 K. At T<25 K, WT and decreases with increasing magnetic field. This behavior is explained as caused by fluctuations of pancake vortices; the latter induce a time dependent random magnetic field which causes the relaxation of nuclear spins.