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Abstract:

The conducting properties of the pressure-induced, layered organic superconductor (BEDT-TTF)(3)Cl-2 . 2H(2)O have been studied at 13.5 and 14.0 kbar using low temperatures, high magnetic fields and two-axis rotation. The observed negative magnetoresistance at 13.5 kbar can be explained by considering Anderson localization within the layers. Further application of pressure destroys the effects of localization.

Abstract:

(BEDT-TTF)3[MnCr(C2O4)3] is the first ferromagnetic molecular metal, in which organic layers of BEDT-TTF alternate with infinite layers of the bimetallic oxalate complex [MnCr(C2O4)3]^-. While the bimetallic layer undergoes a magnetic phase transition into a canted ferromagnetic state at 5.5 K, the metallic character of the conductivity is not affected by the magnetic transition [Nature 408 (2000) 447]. We performed magnetoresistance measurements (B≤17 T) at low temperatures (T≥900 mK) and under hydrostatic pressures of up to 2.0 GPa. Oscillations in the magnetoresistance develop under pressure that can be interpreted as Shubnikov-de Haas oscillations, if an internal magnetic field is taken into account. These measurements can thus be interpreted as a measure of the internal magnetic field in the conduction layer caused by the adjacent magnetic oxalate layers. © 2002 Elsevier Science B.V. All rights reserved.

Abstract:

A brief review of some of the arguments pointing towards the possibility of organic conductors of the form alpha-(BEDT-TTF)(2)MHg(SCN)(4) (where M = K, Tl and Rb) being candidates for Frohlich superconductivity is given. (C) 2002 Published by Elsevier Science B.V.

Abstract:

Peaks in the interlayer magnetoresistance of the layered superconductor kappa-(BEDT-TTF)(2)Cu(NCS)(2) are observed in the presence of an exactly in-plane magnetic field. The existence of these resistance peaks implies the presence of a three-dimensional Fermi surface extending in the interlayer region. Analysis of the width of the peaks yields a value for the interlayer transfer integral. (C) 2002 Elsevier Science B.V. All rights reserved.

Abstract:

The interlayer transfer integrals of various organic superconductors have been deduced using high-magnetic-field techniques. The measurements demonstrate the inappropriateness of criteria used to denote incoherent interlayer transport.