  We experimentally confirmed that the spin-orbit lengths of noble metals
obtained from weak anti-localization measurements are comparable to the spin
diffusion lengths determined from lateral spin valve ones. Even for metals with
strong spin-orbit interactions such as Pt, we verified that the two methods
gave comparable values which were much larger than those obtained from recent
spin torque ferromagnetic resonance measurements. To give a further evidence
for the comparability between the two length scales, we measured the disorder
dependence of the spin-orbit length of copper by changing the thickness of the
wire. The obtained spin-orbit length nicely follows a linear law as a function
of the diffusion coefficient, clearly indicating that the Elliott-Yafet
mechanism is dominant as in the case of the spin diffusion length.
