Dynamics of the resistive state of a narrow superconducting channel in the ac voltage driven regime

Abstract

Within the framework of the time-dependent Ginzburg-Landau equations, the dynamics of the order parameter in narrow superconducting channels of different lengths is investigated in the ac voltage-driven regime. The resistive state of the system at low frequencies of the applied voltage is characterized by the formation of time-periodic groups of oscillating phase-slip centers PSCs. Increasing the frequency reduces the lifetime of these periodic groups. Depending on the length of the channel, the ac voltage either tends to restore the state with a single central PSC in periodic groups or minimizes the number of forming PSCs and induces their ordering in the system. For relatively short channels, a further increase in frequency leads to the suppression of the order parameter without PCS formation. For the systems with the channel length exceeding the specified limit, the formation of PSC starts after a certain time delay which increases rapidly with frequency. The current-voltage characteristics of a relatively short channel at different applied voltage frequencies are calculated. It is found that the current-voltage characteristics exhibit a step-like structure, where the height of the first step is determined by the quadruple value of the Josephson frequency.