ELECTRONIC TRANSPORT IN QUASI-CRYSTALS - AN APPROACH TO SCATTERING WITH FRACTIONAL MULTICOMPONENT FERMI SURFACES

The model for electronic transport in quasicrystals is proposed. Unlik e all previous attempts to explain unusual electronic properties of qu asicrystals by impending localization due to the lack of periodicity i n defectless quasiperiodic lattices, the current theory is focused on phonon and impurity scattering in real, ''dirty'' quasicrystals. The s tandard scattering theory cannot be applied to quasicrystals, due to t heir unusual band structure, namely the fact that the Fermi surface is nearly obliterated. To solve the problem a fractional multicomponent Fermi-surface model has been introduced: the Fermi surface has been vi ewed as consisting of relatively large number of residual tiny electro n and hole pockets, with impurity random potential scattering electron s between different components. Leaving quasiperiodicity aside, the Dy son equations for the scattering time, de conductivity and thermopower have been solved analytically. The theory explains the nearly vanishi ng conductivity, as well as strong temperature dependence of thermopow er and related transport properties.