1. James C. Wyant College of Optical Sciences, University of Arizona, Tucson, Arizona 85721, United States
2. Sandia National Laboratories, Albuquerque, New Mexico 87185, United States
3. Department of Electrical and Computer Engineering, University of Arizona, Tucson, Arizona 85721, United States
4. Department of Materials Science and Engineering, University of Arizona, Tucson, Arizona 85721, United States