Charge density wave paraconductivity in K0.3MoO3

Abstract

The dynamic conductivity has been measured in K0.3MnO3 single crystals in the conducting phase (above 180 K), for the first time over a broad frequency range 1-105 cm-1, using a combination of different spectroscopic techniques. Together with a pseudogap, clearly pronounced excitations are observed below 50 cm-1 for E||b, the direction along which the charge density wave develops. We associate these excitations with charge-density-wave fluctuations which exist even at room temperature and give a collective contribution to the conductivity. For the transverse polarization, E|b, a usual single-particle Drude behavior of the conductivity is observed.