J. Wosnitza et al., THERMODYNAMIC PROPERTIES OF THE ORGANIC SUPERCONDUCTOR KAPPA(L)-(ET)(2)AG(CF3)4-CENTER-DOT-TCE, Solid state communications, 98(1), 1996, pp. 21-25
We present specific-heat, magnetization, and ac-susceptibility measure
ments of the recently discovered organic superconductor kappa(L)-(ET)(
2)Ag(CF3)(4) . TCE, where ET (=BEDT-TTF) stands for bisethylenedithio-
tetrathiafulvalene and TCE is the neutral solvent 1,1,2-trichloroethan
e. We observed a very large anisotropy of the critical field B extrac
ted from ac-susceptibility data in accord with the enhanced ET-layer s
eparation due to the large anions. The strong frequency dependence of
B reveals the weak pinning forces in the material. Magnetization and
specific-heat, C, measurements prove the bulk effect of superconductiv
ity. The linear coefficient of C is gamma approximate to 50 mJ/molK(2)
which is a factor 9 larger than expected from a free-electron picture
. Indications for strong coupling are found.