Influence of Unconventional Current-Phase Relation on Return Current of Tunnel Josephson Junctions

In this study, we carried out the analysis of the return current of Josephson junction with unconventional current-phase relation. We analyzed two types of current-phase relation with additional terms to first harmonic sin phi: the case of second harmonic sin2 phi and the case of fractional term sin phi/2. Numerical methods were employed for the calculations of return current by considering the different amplitudes of the second term in unconventional current-phase relation. It is shown that there is an opposite relation between the return current of Josephson junction with unconventional current-phase relation and the amplitude value of the second term. It can be stated that the return current of Josephson junction can be decreased by increasing the amplitude of the second term.