Another great physics word.

A duoplasmatron is a type of ion source. It operates as follows: a cathode filament emits electrons into a vacuum chamber. A gas, such as argon, is introduced in very small quantities into the chamber, where it becomes charged or ionised through interactions with the free electrons from the cathode, forming a plasma. The plasma is then accelerated through a series of at least two highly charged grids, and becomes an ion beam, moving at fairly high speed from the aperture of the device.