RESUMO
The role of quantum tunneling effect in the electron accretion current onto a negatively charged grain immersed in isotropic plasma is analyzed, within the quasiclassic approximation, for different plasma electron distribution functions, plasma parameters, and grain sizes. It is shown that this contribution can be small (negligible) for relatively large (micron-sized) dust grains in plasmas with electron temperatures of the order of a few electronvolts, but becomes important for nanosized dust grains (tens to hundreds of nanometers in diameter) in cold and ultracold plasmas (electron temperatures at approximately tens to hundreds of Kelvin), especially in plasmas with depleted high-energy "tails" in the electron energy distribution.
RESUMO
It is known that electron thermal motion in the anomalous-skin-effect regime of rf plasma discharges leads to enhancement of rf power absorption by plasma due to the resonant electron-wave interaction, which is a main mechanism of plasma heating in a typical inductively coupled plasma discharge. In this Letter we show, however, that the rf power absorption may be strongly reduced (compared to the Ohmic value) at low frequencies due to the electron thermal motion; an even further reduction occurs due to the nonlinear effects of the rf magnetic field. The absorption reduction occurs for omega
