Low-temperature, low-frequency dielectric response of the pinned charge-density wave in K0.3MoO3

The dielectric response of K0.3MoO3 is investigated at low temperatures (10<T<40 K) and low frequencies (1<<10 kHz). We observe a low-frequency mode that remains well defined at a frequency of 1 Hz (at 33 K). The peak value of the dielectric function 1() associated with this mode grows monotonically as T decreases. We compare our measurements with a recent model of Littlewood that identifies the low-frequency mode with the longitudinal response of the pinned charge-density wave.