Charge density wave
A charge density wave (CDW) is an ordered, "bumpy, sticky" fluid of electrons in a linear chain compound or layered crystal. The electrons within a CDW create a standing wave pattern and can sometimes collectively carry an electric current. The electrons in such a CDW, like those in a superconductor (see superconductivity), can flow through a linear chain compound en masse, in a highly correlated fashion. Unlike a superconductor, however, the electric CDW current often flows in a jerky fashion, much like water dripping from a faucet due to its electrostatic properties. In a CDW, the combined effects of pinning (due to impurities) and electrostatic interactions (due to the net electric charges of any CDW kinks) likely play critical roles in the CDW current's jerky behavior, as discussed in sections 4 & 5 below.