Recent progress on conducting organic charge-transfer salts

The upper temperature for superconductivity in organic conductors has increased from 1 kelvin in 1980, when the phenomenon was discovered in the quasi-one-dimensional cation radical salt tetramethyltetraselenafulvalene phosphorus heptafluoride to 12 kelvin in a new series of organic salts that show nearly two-dimensional electronic properties. These superconductors are attracting interest because of the wide range of new phenomena that they exhibit, including the competition between various ground states, the influence of a magnetic field on a quasi-one-dimensional conductor, the quantization of the Hall effect in a three-dimensional material, the giant magnetoresistance effects related to the two-dimensional nature of the Fermi surface of some materials, and the coherent voltage oscillation of a spin-modulated ground state. Furthermore, there is reason to believe that organic conductors with high superconducting transition temperatures could be produced in the near future. The recent finding of superconductivity in "fullerene" doped with alkali metals supports this optimism.

https://science.sciencemag.org/content/sci/252/5012/1509.full.pdf

The physics of organic superconductors.

Organic−inorganic hybrid films present special challenges and opportunities with respect to potential applications, as well as for the observation of interesting physical phenomena. Although the often disparate characteristics (e.g., solubility and thermal stability) of the two components provide a potential barrier toward forming workable and convenient film deposition strategies, recent results have demonstrated that not only is it possible to develop suitable techniques for these materials but relatively simple processes are often sufficient to yield high quality films. In the current review, some of these recent results on organic−inorganic hybrid films are discussed, with selected examples chosen from among the deposition of sol−gel materials, self-assembled hybrids, Langmuir−Blodgett films, and artificially layered materials. In addition to discussing film-deposition techniques, an effort will also be made, where appropriate, to indicate how the resulting films might be useful for applications such ...

Thin-Film Deposition of Organic−Inorganic Hybrid Materials

We introduce the development of conductive organic molecular assemblies including organic metals, superconductors, single component conductors, conductive films, and conductive liquids, particularl...

Development of Conductive Organic Molecular Assemblies: Organic Metals, Superconductors, and Exotic Functional Materials

Toward systematic understanding of diversity of electronic properties in low-dimensional molecular solids.

Evidence for superconductivity in (BEDT-TTF) 4 (ReO 4) 2 [where BEDT-TTF is bis(eth-ylenedithiolo)tetrathiafulvalenel near 2 K for pressures above 4 kbar is reported. This is the first unambiguous observation of superconductivity in a sulphur-donor organic system. At higher pressures the transition temperature decreases rapidly, dT c,/dP~- 0.3 K/kbar. At low pressures this material exhibits a first-order metal-insulator transition, postulated to result from a change in the arrangement of the anions which are ordered at room temperature.

R. Lagier

Papers

Superconductivity in a new family of organic conductors

Superconductivity in a New Family of Organic Conductors