Condensed Matter Seminars

We discuss the metallic states which are ordered and therefore are not convetional Fermi liquids. In odd-frequency density waves the order parameter vanishes at zero frequency and there is a conventional Fermi surface. However, the frequency dependence of the gap leads to an unusual temperature dependence for various thermodynamic and transport properties. The d-density wave (DDW) is a candidate for the explanation of the pseudogap phase in superconducting cuprates. The gap vanishes at the nodal points, which causes the pure DDW state to be metallic. However, DDW can coexist with either antiferromagnetic or superconducting phases. We consider a microscopic model which favors DDW and do the mean-field-theoretical derivation of the phase diagram (this work is in progress).