Electromagnetic Structure Resonances in Inhomogeneous Plasma Layers

Laser-light absorption and radiation forces are investigated for weakly collisional ($\frac{\nu }{\omega }\ll 1$), rigid, two-step plasma profiles in planar and spherical geometry. For the first step near critical density, the second step above critical, and appropriate step lengths, we find strong absorption even for weakly collisional plasmas. We show, however, that the radiation forces may not permit such profiles to persist in realistic, dynamic situations.