Recent progress in high-pressure studies on organic conductors

Abstract

Recent high-pressure studies of organic conductors and superconductors are reviewed. The discovery of the highest T c superconductivity among organics under high pressure has triggered the further progress of the high-pressure research. Owing to this finding, various organic conductors with the strong electron correlation were investigated under high pressures. This review includes the pressure techniques using the cubic anvil apparatus, as well as high-pressure studies of the organic conductors up to 10 GPa showing extraordinary temperature and pressure dependent transport phenomena.

The Highly Conducting Spin-Crossover Compound Combining Fe(III) Cation Complex with TCNQ in a Fractional Reduction State. Synthesis, Structure, Electric and Magnetic Properties

“…The SCO induced by temperature, pressure or light irradiation is accompanied by the changes in the coordination environment of the metal ion [24][25][26]. The electrical conductivity of the most molecular conductors is very sensitive to external and/or chemical pressure [27,28]. There is an every reason to believe that spin-crossover transition would affect the conductivity at least via a chemical compression or extension arising from structural perturbations in the process of SCO.…”

Electronic properties of Fabre charge-transfer salts under various temperature and pressure conditions

“…[1][2][3] Such phases can be driven both by external (physical) pressure as well as by chemical pressure (see Fig. 1).…”

Multiple superconducting states induced by pressure inMo3Sb7

“…Examples range from metalinsulator transitions [1] to density waves [2] to superconductors [3][4][5][6][7][8]. In Mo 3 Sb 7 itself, superconductivity emerges below a structural phase transition with claims of accompanying magnetic order and spin dimerization [9][10][11], potentially placing it in a growing cohort of exotic superconductors with unconventional pairing mechanisms [4,[12][13][14].…”

“…While ferromagnetic spin fluctuations suppress phonon-mediated superconductivity, the relationship between antiferromagnetic spin fluctuations and phonon-mediated superconductivity is less transparent. This relationship is a key aspect of the physics of systems such as the cuprates, heavy fermion materials, iron pnictides, organic superconductors, rare-earth borocarbides, and the 3d transition-metal compounds CrAs and MnP [3][4][5][6][7][15][16][17][18]. Tuning system properties with pressure, chemical doping and magnetic field can help parse the competing components of χ c,m (q,ω), both in the collective state itself and across a quantum phase transition.…”