Summary: | The transport properties of various systems are studied here in the context of three different models. These are: <br><BLOCKQUOTE>- the disordered Hubbard model applicable to correlated binary alloys with a general disorder, <br>- the Anderson model used in describing the Kondo physics of a quantum dot connected to the external superconducting leads, and <br>- the Ranninger-Robaszkiewicz model applied to the study of optical properties of the system with preformed electron pairs above the temperature of transition to the superconducting state.</BLOCKQUOTE> We calculate the density of states, specific heat, the Wilson ratio and conductivity of the correlated binary alloy with off-diagonal disorder. We investigate the conditions under which the Kondo peak appears in the density of states and in the conductance of a dot coupled to the external superconducting leads. We analyze the effect of the pseudogap on the optical spectra in the high temperature superconductors described by the boson-fermion model.
|