Quantum interference effects in quasi-two-dimensional metals

In connection with two groups of experimental data, a calculation is perfor med of quantum interference corrections in a quasi-two-dimensional metal to conductivity as a function of temperature and magnetic field. For the temp erature dependence a cross-over between a two-dimensional (2D) (higher temp eratures) and 3D (lower temperatures) behavior is obtained. In the 3D limit the relative correction is isotropic. Tn the 2D limit it is extremely anis otropic having a logarithmic dependence in the nb plane, and a power law fo r the c conductivity. The interaction correction to the density of states i s calculated as a function of temperature. A criterion for the crossover fr om 2D to 3D behavior differs strongly from the interference correction, and makes the D limit unlikely. In the 3D limit this correction is proportiona l to root T. Comparison between corrections of different origins favors the interference logarithmic correction for the in-plane conductivity, in agre ement with experiment. The c-axis correction can be of either origin, and i s nonlogarithmic, as observed in some experiments. The dependence of the re lative correction on magnetic field in the 3D limit is always proportional to root H in agreement with experiment, and the coefficient depends only on the orientation of the magnetic field.