Formation of nanoparticles in plasmas

Plasmas are denoted frequently as fourth aggregate state and consist of ionized gases, in which gas atoms are splitted into positively charged ions and electrons. Plasmas containing colloids are called complex or dusty plasmas. In 1994 scientists of the Max-Planck Institute for Extraterrestrial Physics proved that such complex plasmas can self-organize under certain conditions spontaneously to a crystalline-like state, the so called plasma crystal. Plasma crystals are an up to then unknown state in a complex/dusty plasma and can be used to study material characteristics in phase transitions from gas to liquid and solid states. Such three-dimensional plasma crystals can only be produced under microgravity, since on earth gravity squeezes the crystals together. In the year 2001 the plasma crystal experiment on ISS was realized under the leadership of the German Kayser Threde GmbH. The illustration 30 shows a schematic experimental setup, which is similar to the experiment on ISS. The control and the manipulation of the microparticles in the investigated low-temperature plasmas are achieved here by means of a so-called adaptive electrode. This adaptive electrode is composed of several separate, electronically controllable electrode segments. This allows local modifications of the plasma boundary zone.

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