1. Materials Department, University of California, Santa Barbara, Santa Barbara, California 93106, USA
2. EAG Laboratories–Eurofins Materials Science, 628 Hutton St., Suite 103, Raleigh, North Carolina 27606, USA
3. Department of Electrical and Computer Engineering, University of California, Santa Barbara, Santa Barbara, California 93106, USA
4. Intel Corporation, Santa Clara, California 95054, USA