SearcharxivSearch

arXiv subjects

Nada Joo

Publications and source records attributed to Nada Joo.

3 recordsLinked to original sources

Field-induced confinement in (TMTSF)2ClO4 under accurately aligned magnetic fields

We present transport measurements along the least conducting c direction of the organic superconductor (TMTSF)2ClO4, performed under an accurately aligned magnetic field in the low temperature regime. The experimental results reveal a two-dimensional confinement of the carriers in the (a,b) planes which is governed by the magnetic field component along the b' direction. This 2-D confinement is accompanied by a metal-insulator transition for the c axis resistivity. These data are supported by a quantum mechanical calculation of the transverse transport taking into account in self consistent treatment the effect of the field on the interplane Green function and on the intraplane scattering time.

cond-mat.supr-con

Impurity controlled Superconductivity/Spin Density Wave interplay in the organic superconductor : (TMTSF)\_2ClO\_4

The study of the anion ordered (TMTSF)\_2ClO\_4\_(1-x)ReO\_4\_x, solid solution in the limit of a low ReO\_4- substitution level (0<=x<=17%) has revealed a new and interesting phase diagram. Superconductivity is drastically suppressed as the effect of ReO\_4- non magnetic point defects increases following the digamma behaviour for usual superconductors in the presence of paramagnetic impurities. Then, no long range order can be stabilized above 0.1K in a narrow window of substitution. Finally, an insulating SDW ground state in ReO\_4- -rich samples is rapidly stabilized with the decrease of the potential strength leading to the doubling of the transverse periodicity. This extensive study has shown that the superconducting order parameter must change its sign over the Fermi surface.

cond-mat.supr-con

Suppression of superconductivity by non-magnetic disorder in the organic superconductor (TMTSF)2(ClO4)(1-x)(ReO4)x

We present a study of the superconducting properties (Tc and Hc2) in the solid solution (TMTSF)2(ClO4)(1-x)(ReO4)x with a ReO-4 nominal concentration up to x = 6%. The dramatic suppression of Tc when the residual resistivity is increased upon alloying with no modification of the Fermi surface is the signature of non-conventional superconductivity . This behaviour strongly supports p or d wave pairing in quasi one dimensional organic superconductors. The determination of the electron lifetime in the normal state at low temperature confirms that a single particle Drude model is unable to explain the temperature dependence of the conductivity and that a very narrow zero frequency mode must be taken into account for the interpretation of the transport properties.

cond-mat.supr-con