Topological Dislocations and Mixed State of Charge Density Waves.

We discuss the possibility of the “mixed state” in incommensurate charge density waves with threedimensional order. The mixed state is created by applying an electric field perpendicular to the chains. This state consists of topological dislocations induced by the external field and is therefore similar to the mixed states of superfluids (type-II superconductors or liquid helium II). However, the peculiar coupling of charge density waves with the electric field strongly modifies the mixed state compared to conventional superfluids. The field and temperature dependence of the properties of the mixed state are studied, and some experimental aspects are discussed. [S0031-9007(96)01374-9]