Generation of currents and electromagnetic fields in an inhomogeneous laser plasma

Abstract

A physical model of generation of spontaneous magnetic fields and of electric currents in an inhomogeneous laser plasma is developed for a wide range of laser radiation flux densities. It is shown that spontaneous magnetic fields generated in a plasma may be governed not only by the bulk emf sources, but can be influenced significantly by the processes at interfaces in a plasma (for example, at DT fuel–shell, plasma–metal, and other interfaces). A quasistationary approximation is used to formulate the boundary conditions governing the surface sources of spontaneous magnetic fields. A detailed analysis is made of an inhomogeneity of the potential of a double layer and of an effective contact emf in their role as surface mechanisms of generation of spontaneous magnetic fields. Generation of fields and currents is considered analytically in the region of an inhomogeneous interface between two plasmas and in an inhomogeneous laser jet formed as a result of interaction of laser radiation with a conducting target.