CHARGING EFFECTS ON THE CRITICAL-TEMPERATURE OF THE JOSEPHSON-COUPLEDLAYERED SUPERCONDUCTORS

Effects of quantum phase fluctuations on the critical temperature T-c of Josephson-coupled layered superconductors are considered. T-c is sh own to decrease nonlinearly with increasing charge fluctuations. The r esults obtained for the critical temperature by applying the self-cons istent mean field method reveal no phase transition from superconducti ng state to normal metal for a finite value of charging energy. The de struction of the long range phase coherence appeared to occur at asymp totically large values of self-capacitance charging. For the weak quan tum phase fluctuations limit, T-c is obtained to be vary in the interv al of T-c < T-c < T-c((2)), where T-c((2)) is the critical temperatur e for a single superconducting layer evaluated by the mean field theor y, and T-c is the temperature when the phase coherence between the ne arest neighboring layers is lost Since T-c approaches T-c with vanish ing interlayer tunneling integral J(perpendicular to). Calculation of the dependence of the transverse stiffness on the charging energy is c arried out at T=0. The reentrance found can in principle occur at a su fficiently large value of the interlayer tunneling integral J(perpendi cular to) > J(perpendicular to) = kT(c)((2)) where J(perpendicular to) approximate to kT(c)((2)) is the value of J(perpendicular to) when th e superconductor normal metal phase transition takes place. However, t he condition J(perpendicular to) greater than or equal to kT(c)((2)) c ontradicts to the existence of the Josephson coupling between supercon ducting layers. (C) 1998 Elsevier Science B.V.