[1] Univ Calif Los Angeles, Dept Chem & Biochem, Los Angeles, CA 90095 USA
[2] Univ Calif Los Angeles, Calif NanoSyst Inst, Los Angeles, CA 90095 USA
[3] Northwestern Univ, Dept Chem, Evanston, IL 60208 USA
[4] Northwestern Univ, Dept Mat Sci & Engn, Evanston, IL 60208 USA
[5] Intel Labs, Santa Clara, CA 95054 USA
[6] KACST, Natl Ctr Nano Technol Res, Riyadh 11442, Saudi Arabia