1. Pritzker School of Molecular Engineering, The University of Chicago, Chicago, IL 60637, USA.
2. School of Microelectronics, Tianjin University, Tianjin, China.
3. Department of Mechanical and Aerospace Engineering, University of California, Los Angeles, Los Angeles, CA 90095, USA.
4. Department of Computer Science, The University of Chicago, Chicago, IL 60637, USA.
5. Nanotechnology and Science Division, Argonne National Laboratory, Lemont, IL 60439, USA.