Particle-in-Cell Simulation of a Current Free Double Layer

A current free low pressure plasma expanding in a diverging magnetic field can spontaneously generate current free double layers (CFDL) ^1,2 . The energetic ion beam generated at the downstream of the CFDL gives a new perspective to the study of such double layers ³ . This supersonic ion beam can explain different space and laboratory plasma phenomena ⁴ , from the acceleration of the plasma particles in the aurora to the design of a helicon double layer thruster.