We have used electromodulated infrared transmission to image charge-density-wave strains in blue bronze. Two components of the strain are identified: a bulk strain, which appears throughout the crystal above an applied voltage ${\mathit{V}}_{\mathit{P}}$, and a contact strain, which appears within ≊100 μm of the contacts with the onset of nonlinear current at ${\mathit{V}}_{\mathit{T}}$≳${\mathit{V}}_{\mathit{P}}$. The two components have very different voltage, frequency, and temperature dependencies.

• Received 14 July 1995

DOI:https://doi.org/10.1103/PhysRevB.52.R11545