Spatially resolved studies of charge-density-wave dynamics and phase slip in NbSe3

We have performed spatially resolved measurements of the charge-density-wave (CDW) response to bipolar current pulses. These measurements directly yield the distribution of the CDW phase slip, the temporal evolution of the CDW elastic-force and strain profiles, and the local relationship between the phase-slip rate and strain. The steady-state elastic-force profile is strongly coupled to the phase-slip distribution. This coupling increases the CDW strain gradient near the current contacts, and reduces the size of the region in which significant phase slip occurs. Simulations of a model for CDW dynamics that includes the elastic-force-phase-slip coupling provide an excellent quantitative account of the complex spatiotemporal response. Our results imply a revised interpretation of the pulse-sign memory effect, establish the connection between CDW strains and the phase-slip voltage, provide insight into the processes underlying phase slip, and have broad implications for the understanding of previous transient and steady-state measurements in CDW systems.