1. Department of Physics and Optical Science; Center for Optoelectronics and Optical Communications; University of North Carolina at Charlotte; Charlotte NC 28223-0001 USA
2. Department of Radiophysics; University of Nizhny Novgorod; Nizhny Novgorod 603950 Russia
3. Air Force Research Laboratory; Sensors Directorate; Wright-Patterson AFB OH 45433 USA
4. Air Force Research Laboratory; Materials and Manufacturing Directorate; Wright Patterson AFB OH 45433 USA