A review of recent laboratory double layer experiments

Recent developments in laboratory double layers from the late 1980s to the spring of 2007 are reviewed. The paper begins by a lead up to electric double layers in the laboratory. Then an overview of the main double layer devices and properties is presented with an emphasis on current-free double layers. Some of the double layer models and simulations are analysed before giving a more complete description of current-free double layers in radiofrequency plasmas expanding in a diverging magnetic field. Astrophysics double layers are briefly reported. Finally, applications of double layers to the field of plasma processing and electric propulsion are discussed.