The simulation of current-voltage characteristics and the dynamic conductivity of the ballistic contacts based on superconductors with weak oscillation order parameter

Abstract

In the framework of the model of multiple Andreev reflections of quasiparticles (Averin-Bardas model) the currentvoltage characteristics and the dI dV -spectra of dynamic conductivity of ballistic contacts "superconductor -normal metal -superconductor" (SNS) in high transparency mode (for D = 0,9÷0,98) were calculated. In this mode the energy gap of superconductors comprising SNS-contact is oscillatory in the energy range 60÷100 meV due to the strong electron-phonon interaction. The features of subharmonic gap structures are revealed in the considered contacts at voltages 4 = 2 4 V e, 5 = 2 5 V e, 6 = 2 6 V e and 7 = 2 7 V e as transforming minimums into maximums at the increase of transparency coefficient from 0,9 to 0,98 (or reduction of the barrier height from 0,33 to 0,144). The results satisfactorily correlate with experimental data.