Effects of randomness on the critical temperature in quasi-two-dimensional organic superconductors

The effects of non-magnetic disorder on the critical temperature T_c of organic weak-linked layered superconductors with singlet in-plane pairing are considered. A randomness in the interlayer Josephson coupling is shown to destroy phase coherence between the layers and T_c suppresses smoothly in a large extent of the disorder strength. Nevertheless the disorder of arbitrarily high strength can not destroy completely the superconducting phase. The obtained quasi-linear decrease of the critical temperature with increasing disorder strength is in good agreement with experimental measurements.