1. Department of Electrical and Computer Engineering, University of Virginia, Charlottesville, Virginia 22904, USA
2. Department of Materials Science and Engineering, University of Virginia, Charlottesville, Virginia 22904, USA
3. Northrop Grumman Corporation, Rolling Meadows, Illinois 60008, USA
4. U.S. Army RDECOM CERDEC Night Vision and Electronic Sensors Directorate, Fort Belvoir, Virginia 22060, USA