Negative resistance in charge-density-wave materials

The observation of absolute negative resistance is one of the most surprising and unexpected phenomena in the experimental, study of microscopic Charge-Density-Wave (CDW) dynamics. The moving CDW pumps single-particle charge carriers in the opposite direction to the rest of the sample. This new phenomenon only occurs on typical length scales of a micrometer and less. The origin of the negative resistance is attributed to the different forces that the deformed CDW and single-particles feel: the force on the CDW is merely caused by an electric field, whereas the single-particle current is governed by a difference in electro-chemical potentials.