Static charge coupling of intrinsic Josephson junctions

A microscopic theory for the coupling of intrinsic Josephson oscillations d ue to charge fluctuations on the quasi-two- dimensional superconducting lay ers is presented. Thereby in close analogy to the normal state the effect o f the scalar potential on the transport current is taken into account consi stently. The dispersion of collective modes is derived and an estimate of t he coupling constant is given. It is shown that the correct treatment of th e quasiparticle current is essential in order to get the correct position o f Shapiro steps. In this case the influence of the coupling on de propertie s like the I-V curve is negligible. (C) 2001 Elsevier Science B.V. All righ ts reserved.