1. Department
of Physics, Ben-Gurion University of the Negev, P.O. Box 653, 8410501 Beer-Sheva, Israel
2. Department
of Chemistry, North Carolina State University, 2620 Yarbrough Drive, Raleigh, North Carolina 27695-8204, United States
3. Adámas Nanotechnologies, Inc., 8100 Brownleigh Drive, Raleigh, North Carolina 27617, United States