The authors report NMR measurements of the ${}_{}{}^{93}{}_{}{}^{}\mathrm{Nb}$ resonance in the charge-density-wave (CDW) conductor ${\mathrm{NbSe}}_3$ on aligned, multicrystalline samples. They have observed the resonance with and without current flow in the sample at temperatures above 59 K, where a single incommensurate CDW is present. Results include (1) a demonstration that the CDW is not discommensurate, (2) quantitative measurements of CDW displacements below threshold, and (3) evidence, including current-induced motional narrowing, of CDW motion throughout the entire sample, above the threshold.

• Received 5 December 1985

DOI:https://doi.org/10.1103/PhysRevLett.56.663