1. Department of Electro-Optics and Photonics, University of Dayton, Dayton, Ohio 45469, USA
2. Air Force Research Laboratory, Wright-Patterson AFB, Ohio 45433, USA
3. Department of Mechanical Engineering, Stanford University, Stanford, California 94305, USA
4. KBR, Beavercreek, Ohio 45431, USA
5. Department of Physics, University of Dayton, Dayton, Ohio 45469, USA