Control of fine particles by time-averaged external forces in plasmas

A technique for the control of fine particle behavior is developed and demonstrated experimentally. In this method positive pulses are applied to two point-electrodes placed with some distance in plasmas containing fine particles. When the positive pulses are applied to these electrodes alternatively with a repetition period that is shorter than the particle response time, the particles feel only time-averaged force because of their large mass and are gradually transported toward the middle point between two point-electrodes wherever they are distributed initially. This method is quite effective for converging fine particles in the plasma