ANOMALOUS TEMPERATURE-DEPENDENCE OF THE PHASE-COHERENCE LENGTH FOR INHOMOGENEOUS GOLD-FILMS

Magnetoresistance measurements as well as transmission-electron-microscopy investigations are carried out for thin gold films of varied topography. For gold films with percolative structure, we find an anomalous temperature dependence of the phase-coherence length L-phi(T), if the percolation correlation length xi-p > L-phi(T). This can be understood in terms of anomalous diffusion. Moreover, comparing these results with L-phi(T) for nonpercolating (homogeneous) gold films yields critical exponents of two-dimensional percolation, quantitatively.