Kinetic Theory of Electrostatic Surface Waves in a Magnetized Plasma Slab

ABSTRACT

The dispersion relation of electrostatic surface waves propagating in a magnetized plasma slab is derived from Vlasov-Poisson equations under the specular reflection boundary condition. We consider the case that the static magnetic field is parallel to the plasma-vacuum interface and the surface wave propagates obliquely to the magnetic field on the parallel plane. We find that the specular reflection boundary conditions on the plasma slab-vacuum boundaries can be satisfied, even in a magnetized plasma, by simple extension of the electric potential into the vacuum region, due to the inherent symmetry of the distribution function. Utilizing an invariance property of the kinetic surface wave solution, it is shown that the two-mode structure of the surface wave yields the symmetric and anti-symmetric modes. The kinetic dispersion relation is checked against the dispersion relations obtained from fluid equations and shows complete agreement.