[1] Univ Dayton, Dept Elect & Comp Engn, Dayton, OH 45469 USA
[2] Univ Dayton, Electroopt Program, Dayton, OH 45469 USA
[3] MIT, Dept Mech Engn, Cambridge, MA 02139 USA
[4] Univ S Florida, Dept Phys, Tampa, FL 33620 USA
[5] Alabama A&M Univ, Dept Phys, Normal, AL 35762 USA