1. Department of Electrical and Computer Engineering, Rice University, Houston, Texas 77005, United States
2. Department of Physics and Astronomy, Rice University, Houston, Texas 77005, United States
3. Sandia National Laboratories, Livermore, California 94551, United States
4. Department of Chemistry, Rice University, Houston, Texas 77005, United States
5. King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia