TRANSITION OF CHARGE-DENSITY-WAVE CONDUCTORS INTO A GLASSY-LIKE STATE

We have found that the real part of the dielectric constant of the quasi-one-dimensional conductors with a charge density wave (CDW) shows a peak in the low temperature range (T < 40 K). This peak can only be detected at frequencies below 100 kHz and its position is shifted to lower temperatures with decreasing frequencies. In the same temperature range the relaxation time grows drastically. This result provides a direct experimental evidence for a transition of the CDW into a glassy-like state at low temperatures. We suggest a qualitative model which describes the behaviour of a CDW near this transition.