Model of charge-density-wave current conversion and phase-slip dynamics in mesoscopic samples

Abstract

A microscopic model of collective-to-normal current conversion in mesoscopic charge-density-wave (CDW) conductors is presented. The current conversion is described in terms of phase slips induced by CDW strain and thermal fluctuations. Cores of phase slips are described as dynamic solitons with suppressed order parameter centered at individual chains near current contacts. The size of the cores is of the order of the amplitude coherence length, and they are surrounded by long-range perturbations of the CDW phase and of electric field induced by the CDW distortion. If the contact spacing is shorter than decay length of the long-range perturbations, the dynamics of phase slips at opposite contacts is correlated. In this case the phase-slip voltage decreases with the contact spacing decreasing. The results are in qualitative agreement with experimental study of current conversion in submicron ${\mathrm{NbSe}}_{3}$ wires. In the limit of a large applied electric field a decrease of the phase-slip voltage is predicted even at large distances between current contacts.