"Exploring the 4th state of matter"
PHYSICS DEPARTMENT COLLOQUIUM
Exploring the 4th state of matter Jörg Winter
Bochum University, Bochum, Germany
A plasma, i.e. partially or fully ionized matter is often called "4th state of matter".
It is characterized by collective behavior - all particles are coupled to each other via
the Coulomb force. Plasmas have unusual properties, which may be manipulated and tuned by
external means like electric and magnetic fields, the type of power coupling gas pressure,
interaction with intense light pulses, just to name a few.
Low-temperature plasmas usually have a small degree of ionization - nevertheless they
possess most interesting properties making them ideal tools for many applications like
deposition of functional thin films, dry etching, lighting, and, most recently, for
applications in the bio-medical field. The enormous potential is largely due to the
non-equilibrium character of these plasmas, i.e. highly energetic electrons and cold
ions and neutral gas.
The presentation will give a short introduction into the diverse world of plasmas and
then concentrate on the discussion of low-temperature plasmas and on some of their
April 17, 2013 (Wednesday)