1. Center for Bio/Molecular Science and Engineering, Code 6900, U.S. Naval Research Laboratory, Washington, D.C. 20375, United States
2. Optical Sciences Division, Code 5600, U.S. Naval Research Laboratory, Washington, D.C. 20375, United States
3. KeyW Corporation, Hanover, Maryland 21076, United States
4. George Mason University, College of Sciences, Fairfax, Virginia 22030 United States