Resistively and capacitively shunted Josephson junctions model for unconventional superconductors

An array of resistively and capacitively shunted Josephson junctions with nonsinusoidal current-phase relation is considered for modelling the resistive transition in high-T c superconductors. The emergence of higher harmonics, besides the sinusoid I c sin ⊘, is expected for dominant d-wave symmetry of the Cooper pairs, random distribution of potential drops and dirty grains, or in nonstationary conditions. We show that additional cosine term acts by modulating the global resistance, due to the weak-links whose transition occurs through mixed superconductive-normal states.