Nuclear spin diffusion in the semiconductor TlTaS3

We report on a 203Tl and 205Tl nuclear magnetic resonance study of the chain ternary semiconductor TlTaS3. We show that spin-lattice relaxation in this compound is driven by two contributions, namely by interactions of nuclear spins with thermally activated carriers and with localized electron spins. The latter mechanism dominates at lower temperature; at that, our measurements provide striking manifestation of the spin-diffusion-limited relaxation regime. The experimental data obtained allow us to estimate the spin diffusion coefficient.