1. Department of Electrical and Computer Engineering, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA
2. Terahertz Materials Analysis Center, Department of Physics, Chemistry and Biology (IFM), Linköping University, SE 58183 Linköping, Sweden
3. Air Force Institute of Technology, Wright-Patterson Air Force Base, Ohio 45433-7765, USA
4. Air Force Research Laboratory, Sensors Directorate, Wright Patterson AFB, Ohio 45433, USA
5. KBRwyle, Dayton, Ohio 45431, USA
6. Department of Physics and Astronomy, University of Nebraska-Lincoln, Theodore Jorgensen Hall, 855 North 16th Street, Lincoln, Nebraska 68588-0299, USA
7. Leibniz Institute for Polymer Research, 01069 Dresden, Germany