The U.S. Air Force allocates some $10 million a year for research geared toward satellite protection. Of that amount, $2 million is dedicated to low-temperature plasma studies...
Poke a finger inside Laroussi’s tabletop plasma-generating apparatus and all you’ll get from the
bluish, pilot-light-like ionized gas is a slight tingle. But the harmless sensation is misleading, since it doesn’t give a complete picture of plasma’s power. Depending on how a plasma is "tuned," or how it is made more dense by increasing its frequency, it could ward off microwave bursts and discharges from ground-based, energized sources of potential damage and disruption.
Swirling in and around one another, a plasma’s charged particles interact constantly, giving rise to localized attractions or repulsions. External energy splashing against the plasma --- say, from a potentially disabling, concentrated burst of microwaves, or perhaps even from certain varieties of particle-beam weapons fired from military bases on Earth -- could be caught up within the plasma’s complex electromagnetic fields to be dissipated completely or deflected into space.
"In theory, a plasma could deflect a particle beam or laser attack," Laroussi says. "It depends on what you’re shooting at it and how high you can tune the
plasma frequency. That doesn’t mean it’s easy or practically achievable, particularly with a cold plasma. It’s a tough requirement to meet at present."
Cloaking mirrors
A nearer-term application is cloaking. With the proper adjustments, a plasma can be made into a kind of energy mirror, reflecting back or away incoming electromagnetic waves, such as those emitted from ground-based radars. In essence, any spacecraft outfitted with this kind of plasma field would be completely cloaked from the probing attentions of radar operators.
"The idea is to deflect or absorb the energy completely," Laroussi said. "If you absorb the energy --- completely dissipating it within the plasma --- the radar doesn’t see anything. Nothing reflects back."
Less immediately space-like, but no less practical, are
biological applications. Cold plasmas allow for rapid decontamination of clothing, equipment or personal gear. In disrupting the integrity of cell membranes, the plasmas appear to offer a rapid, simple and inexpensive means of destroying even the hardiest bacterial spores. At present, sterilization time can run hours; use of a cold plasma could sanitize in mere minutes.
http://www.space.com/businesstechnology/technology/cold_plasma_000724.html