  It is shown experimentally that the photodetachment yield of surplus
electrons created by plasma-induced charging of non-conductive surfaces of
dielectric materials depends on the initial surface charge density and do not
correlate with the tabulated affinity values of these materials. This
unexpected result obtained using laser-stimulated photodetachment for fused
silica, boron nitride, and alumina, is critically important for the
understanding of charging and discharging dynamics, secondary electron
emission, and photoemission effects affecting plasma-wall interactions relevant
to surface and capacitively coupled discharges, dusty plasmas, electrostatic
probe diagnostics and applications for plasma processing of materials, plasma
propulsion and gas breakdown.
