Drude Metallic Response of Polypyrrole.

Abstract

The very highly conducting state of polypyrrole is investigated. A Drude metallic response, similar to the behavior of usual metals, is determined, based on the coincidence of dc and microwave conductivities, measurement of a huge and negative microwave dielectric constant, and the optical determination of an unusual plasma frequency in the far ir. Only a fraction of the conduction electrons participate in the Drude behavior. The real part of the dielectric function shows a second plasma frequency in the near ir, attributed to the remaining conduction electrons, confined due to a lack of homogeneous, three-dimensional order.