The charge density wave structure near a side metal contact

(Received 29 November 1991, accepted 10 January 1992)

Abstract
We consider the structure of a distorted Charge Density Wave (CDW) near a side contact to a metal. We show that the electric field screening and the charge penetration proceed via inhomogeneous distribution of solitons and/or dislocations. In the presence of these topological defects we study selfconsistent equations for elastic and Coulomb fields. For high temperatures we find the soliton density distribution through the sample depth and calculate the capacitance. For low temperatures and concentrations we study in details the fields and induced surface charges for a single dislocation near the metal surface. At low temperatures and high concentrations a periodic structure of dislocations emerges at some critical voltage between the metal and the CDW. At small charges near threshold voltage the dislocations are far separated and, unexpectedly, deeply located. So the contact region naturally provides both generation and storage of topological defects. With the longitudinal current being applied, these defects will nuceate phase-slips for the CDW sliding.