1. Department
of Chemistry and Chemical
Biology, and Center for High Technology Materials, University of New Mexico, Albuquerque, New Mexico 87131, United States
2. Nonlinear
Physics Centre, Research School of Physics
and Engineering, The Australian National University, Canberra, ACT 0200, Australia
3. Center for Integrated
Nanotechnologies, Sandia National Laboratories, Albuquerque, New Mexico 87185, United States