Impurity Effect on Superconducting Properties in Molecular Substituted Organic Superconductor $\kappa$-(ET)${}_2$Cu(NCS)${}_2$

Abstract

We report an impurity effect in the organic superconductor $\kappa$-(ET)${}_2$Cu(NCS)${}_2$ by substitution of the ET molecule with an analogue, bis(methyleneditio)tetrathiafulvalene (MT). The superconducting transition temperature decreases with increasing substitution. The in-plane magnetic penetration depth is enhanced with substitution, which is quantitatively attributed to the decrease in the in-plane mean free path. The enhancement of the penetration depth can also explain the reduction of the effective pinning in terms of the condensation energy.

4 pages, submitted to J. Phys. Soc. Jpn

References in corpus (2)

• The Dependence of the Superconducting Transition Temperature of Organic Molecular Crystals on Intrinsically Non-Magnetic Disorder: a Signature of either Unconventional Superconductivity or Novel Local Magnetic Moment Formation
• Real space imaging of the metal - insulator phase separation in the band width controlled organic Mott system $\kappa$-(BEDT-TTF)${}_2$Cu[N(CN)${}_2$]Br