Organic superconductors isotope effect

Komatsu T, Matsukawa N, Nakamura T, Yamochi H, Saito G (1992) Isotope effect on physical properties of BEDT-TTF based organic superconductors. Phosphorus Sulfur Silicon Relat Elem 67 295-300... 

Ito H, Watanabe M, Nogami Y, Ishiguro T, Komatsu T, Saito G, Hosoito N (1991) Magnetic determination of Ginzburg-Landau coherence length for organic superconductor /c-(BEDT-TTF)2X (X = Cu(NCS)2, Cu[N(CN)2]Br) effect of isotope substitution. J Phys Soc Jpn 60 ... 

Isotopic shift experiments are also important in organic superconductors, but their interpretation in all three classes must be treated with great caution, as many extrinsic effects may affect Tc in these materials. The isotopic deuterium labeling of methyl or ethylene groups located at the outskirt of the molecule may result in a significant Tc shift, which can be related to the known very large pressure coefficient of Tc in organic su-... 

As a further test as to whether the behavior is conventionally superconducting or not, the isotope effect of organic superconductors has been studied at length. Prom the simple BCS formula (2.6) it follows that should increase with increasing Debye temperature which is to a first approximation proportional to (see also Chap. 1). However, the results of isotope... 

The coherence length in the organic superconductors is of the order of a lattice constant (as it is for the ceramic oxide superconductors). The organic superconductors are of type II (they have two critical fields). The dimensionality is between 1 and 2 (it is 3-D for the fullerides). For organic superconductors, the isotope effect results are unclear it is not certain which phonon modes are important for the superconductivity. 

Schwenk, H., Hess, E., Andres, K., Wudl, F., and Aharon-Shalom, E., Isotope effect in the organic superconductor (TMTSF)jC104, Phys. Lett., 102A, 57, 1984. 

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