Evidence in Support of Dislocation-Mediated Melting of a Two-Dimensional Electron Lattice

Abstract

A sharp peak occurs in the temperature-dependent power absorbed by a two-dimensional sheet of electrons for temperatures near the melting transition when the electrons are driven parallel to the underlying helium surface with an ac voltage. The temperature at the absorption maximum is measured as a function of driving frequency, and the results are interpreted as the power absorbed by dislocations which move in response to the externally imposed stress.