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A brief review of recent results on interlayer tunneling spectroscopy of layered high temperature superconductors (HTS) and charge density wave (CDW) materials is presented demonstrating high capability of this method for studies of both electron condensed states. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

We review recent NMR studies of a layered organic superconductor of the (BEDT) 2 X family. First the normal state prop erties are discussed. The central issue is the importance of the interplay between antiferromagnetism and superconductivity in these materials demonstrated by the observation of a pseudogap developing prior to the superconducting transition. The use of high pressure to tune the amplitude of AF fluctuations enables us to draw a general phase diagram of the family. In the second part the NMR experiments in the superconducting state are presented. One of the fundamental questions addressed by these experiments is the symmetry of the order parameter related to the pairing mechanism. The most spectacular NMR measurements are those performed in the lock-in state, which give access to the density of superconducting excitations at low energy. These experiments suggest that the pairing state may be unconventional featuring an anisotropic superconducting gap, possibly with nodes.

We review approach of the solid state physics to the electronic and optical properties of conducting polymers. We consider their generic features as 1D semiconductors as well as the particularities of the phenyl group. We are taking efforts to bring together the solid state theory for polymers and the quantum chemistry of oligomers.