Elastic properties of linear charge density wave materials in the regime of nonlinear conduction

Abstract The Young's moduli E of TaS 3 , (TaSe 4 ) 2 I, and NbSe 3 are found to soften when the samples are subjected to voltages V in excess of the threshold V T for nonlinear electrical conduction by sliding charge density waves. The voltage dependences of E are similar to the voltage dependences of the differential resistance and of the dielectric constant. The difference in stiffness for V T and V >> V T is ascribed to decoupling of distortions of the charge density wave from those of the underlying lattice.