In-situ measurement of dust charge density in nanodusty plasma

Abstract A dust grain immersed in a low-pressure gas discharge obtains permanent negative surface charge due to the high mobility of electrons compared that ions. This essentially governs all fundamental processes dusty and complex plasmas involving grains, neutrals, (an)ions and—consequently—virtually industrial applications these types are affected steered by it. In this work, we have measured application laser-induced electron detachment from nanosized grains concert with microwave cavity resonance spectroscopy laser light extinction. The main result is release governed photodetachment rather than thermionic emission, recharging occurs on timescales well agreement orbital-motion-limited (OML) theory. total density residing inside volume follows saturation signal, which was used combination values derived extinction measurements estimate mean charge. 140 nm (average) diameter work obtained be range 273 – 2519 elementary charges, lower bound matches analytical predictions using OML