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The article focuses on the detection of superconductivity in organic compounds. The structural building blocks of these organic compounds fit closely together in quasi-one dimensional structures. It requires small amount of energy to partially fill or partially open a valence energy bond. The valence electrons can easily propagate current through these structures.

De toute part émergent des propositions pour évaluer les scientifiques à partir des données bibliométriques de leurs publications. Ces nouvelles méthodes peuvent être utilisées, dans la mesure où elles sont directement liées à la reconnaissance des auteurs par leurs citations, au travers de leur indice de Hirsch ou de Egghe et non à la popularité du journal (facteur d’impact). Un petit exercice basé sur des scientifiques reconnus et de différentes communautés montre comment l’indicateur de Egghe, en particulier, peut être un complément utile à l’indispensable évaluation par les pairs.

Over the second half of this century, scientists have made remarkable progress in understanding the properties of electrons in condensed matter. This success has primarily been due to describing the electrons in terms of a collection of states, with each state labelled by its momentum and spin. Electrons are fermions and therefore obey the Pauli exclusion principle, which means that two fermions cannot have the same momentum and spin quantum numbers. The exclusion principle forces electrons to occupy a range of momentum states up to a so-called Fermi surface. In three dimensions the Fermi surface is a sphere.

The magnetoresistance of quasi-1D two-chain organic conductor HMTSF-TCNQ (hexamethylenetetraselenafulvalene-tetracyanoquinodimethane), which shows charge density wave transition at ambient pressure, was studied under pressure up to 27 T and 31 T, in two high field facilities. We found a kink structure in the magnetoresistance reminiscent of field-induced spin density wave at an intermediate pressure of 1.5 GPa between 0 and 2 GPa. We speculate that these are successive quantum phases induced by magnetic field.