Electromodulated infrared transmission in blue bronze

Abstract

The infrared transmittance of the quasi-one-dimensional charge-density-wave (CDW) material blue bronze (${\mathrm{K}}_{0.3}$${\mathrm{MoO}}_{3}$) is observed to be affected by an applied electric field. The effect is interpreted in terms of changes in free carrier absorption resulting from surprisingly large changes in the density of quasiparticles which screen the CDW polarization at electrical contacts. The magnitude of the screening charge has a maximum at 110 K, and is thermally activated below this temperature.