Dimensional crossover of quantum interference effects in thin quasicrystalline Al-Cu-Fe films

摘要

We present a study of the electrical transport properties of thin i-Al-Cu-Fe films. We observe clear signatures of a dimensional crossover in the temperature and magnetic field dependence of the conductivity for films thinner that approx=10~3 A. In particular for the thinnest sample the magnetoconductivity is strongly anisotropic, as is expected for the weak localisation contribution in two dimensions. These experiments show direct qualitative manifestations of the disorder induced quantum interference effects occurring in quasicrystals. Estimates of the electronic microscopic parameters are in accordance with those obtained in bulk samples. Their values and significance are discussed.