Low-frequency dielectric response of the charge-density wave in orthorhombicTaS3

Abstract
We have studied the dielectric response of the charge-density wave (CDW) in orthorhombic TaS3 in the frequency range 5 Hz to 5 MHz as a function of ac signal amplitude, and at temperatures between 73 and 128 K. The CDW response is strongly dependent on signal amplitude for rms signals greater than 10% of the threshold voltage for nonlinear transport. Divergent dielectric constants at low frequency are observed for relatively large signal amplitudes. The small signal response reveals the dramatic disappearance of a low-frequency relaxation between 115 and 65 K.