1. NanoScience Technology Center and Department of Physics, University of Central Florida, Orlando, Florida 32816, United States
2. Department of Physics, University of Washington, Seattle, Washington 98195, United States
3. Department of Materials Science and Engineering, and Advanced Materials Processing and Analysis Center, University of Central Florida, Orlando, Florida 32816, United States
4. Department of Physics, University of South Florida, Tampa, Florida 33620, United States
5. School of Electrical Engineering and Computer Science, University of Central Florida, Orlando, Florida 32826, United States