SPIN FLUCTUATIONS IN S=1 2 DOUBLE-LINEAR-CHAIN GAMMA-LIV2O5 STUDIED BY LI-7 NMR/

The nuclear spin-lattice relaxation rate (1/T-1) of Li-7 nuclei has be en measured in a spin S=1/2 double-linear-chain system with exchange i nteraction J=308 K, gamma-LiV2O5, in the temperature range from 280 K down to 0.5 K. We observed that 1/T-1 shows the minimum at about 0.1 J . The increase of 1/T-1 below and above 0.1 J are well explained by co nsidering the contribution from the staggered-spin fluctuation and the uniform-spin fluctuation, respectively. Especially, the increase of 1 /T-1 below 0.1 J suggests the appearance of the logarithmic correction effect which has been recently predicted by theoretical works in an i sotropic Heisenberg linear chain.