1. Department of Materials Science and Engineering, University of Virginia, Charlottesville, Virginia 22903, USA
2. Plasma Physics Division, Naval Research Laboratory, 4555 Overlook Ave. SW, Washington DC 20375, USA
3. ASEE Postdoctoral Research Associate, U.S. Naval Research Laboratory, 4555 Overlook Ave. SW, Washington, DC 20375, USA
4. Department of Mechanical Engineering, University of Virginia, Charlottesville, Virginia 22903, USA
5. Department of Physics, University of Virginia, Charlottesville, Virginia 22903, USA