Muon diffusion and spin dynamics in copper

We have studied the quantum diffusion of positive muons in pure copper over the temperature range 12 mK≤T≤150 K using the technique of muon-spin relaxation. The rate of diffusion has been deduced from its effect upon the muon-polarization function. The measurements were made in a weak longitudinal external magnetic field, where the spin relaxation has proved to be the most sensitive to the muon hop rate below 150 K. Our results for the behavior …