1. Department of Physics and Astronomy, Rice University, Houston, TX 77005 USA.
2. Department of Electrical and Computer Engineering, Rice University, Houston, TX 77005 USA.
3. Department of Chemistry, Rice University, Houston, TX 77005 USA.
4. Rice Quantum Institute, Rice University, Houston, TX 77005 USA.
5. Center for Nanoscale Science and Technology, Rice University, Houston, TX 77005 USA.